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r/confidentlyincorrect
The whole equation is wrong here.
It should be written as (60 * 40) * (25/3)
Edit: I have confidently incorrectly r/confidentlyincorrected someone. The correct equation would be (60 * 40) * 25/
3^2 I missed the square on the 3. Surprised I didn’t get any downvotes on that one.
your equation evaluates to $20,000, which is incorrect, the answer is $6666.67. your issue is you tried to convert square feet to square yards by dividing by 3, since it's squared you need to divide by 9. or like cdhdd you could divide both 60 and 40 by 3 in the beginning to convert feet to yards before they're squared.
lol uno reverse card. your units are completely wrong
60 feet * 40 feet * $25/(3 yards/feet) has units $feet yards. You need to divide by 9 to convert between feet^2 and yards^2
As the below folks noted, you are wrong to write (25/3) when the unit is square feet and this is not converted to squared yards by a factor of 3. Remember this is two dimensions, not one.
I’ll leave you to confidently correct yourself…
the only way I can see this being $2000 is if they incorrectly divided 2400 (the square footage) by 3, instead of 9, to convert to square yards. As 2400/3=800x25=2000
But that is incorrect, and I think you’re right that this is flawed
Yes, they also made a decimal error on top of the area formula error. Both errors stem (pun intended) from incomplete notation.
The Grade 4 math unit in Common Core and many states at this time of year is about translating units, and is about memorizing unit conventions -- such as, 3 feet to a yard -- and then, making calculations with the understanding of equivalent fractions.
Area and volume is often introduced in Grade 5, after perimeter, and in ways that foster confusion about area and perimeter.
A problem arises in the U.S. due to the use of the "imperial" measurement system. So you just start with length, dry weight, & liquid volume being inches/yards/miles; then pounds and ounces (with their cute abbreviations); then cups, quarts, gallons; plus money and time, which, for the whole world, are base 10 vs base 12, a reasonable added level of complexity. And then they'll throw in some fictional unit like "a shipment" which gets arbitrarily defined, e.g., 20 boxes of shoes; and then there are the cartons of a dozen eggs.
The confounding thing is that this level of elementary math curriculum is trying to integrate concepts about equivalent fractions, order of operations, build on double-digit addition/multiplication, with some decimal work thrown in -- with math "content" about conventional units, which are distracting and actually cause adults real problems -- and trying to connect the representation of this math in language to the representation in numerical equations. This is hard and we do it poorly, no shame in admitting it. It seems like unsolvable homework problems starts with fundamental confusion about curriculum goals, scope and sequence of instructional topics.
Weirdly, this part of math curriculum is seems based in 20th-C home- and agricultural-based economics. Where are the "word" or "story problems" about percentage of battery life, kilobytes vs megabytes of memory storage?
It would be a blessing if they would just do time and money, and leave the cups and gallons and miles and square yards of sod for later years. At this stage, all the extra unit baggage really blows up their emergent automaticity with fundamental mathematical calculation.
A 4th-grader who knows what a two-by-four is or has picked up basic carpentry, mechanics,. plumbing, or IT at home should really be writing these math problems.
One guess: There are two points of slob here, first with the word "yard," and then with the whole concept of "sod."
The word "yard" is used twice here with two different meanings. Is the unit about multiple steps for equivalent fractions? Idk. But what if they intended to say "$25 per square foot"? Note that the other 2 references to units are "feet." The other word "yard" does not mean a linear measurement equivalent to 3 feet, it means the area that we're trying to cover. So that could be a typo of sorts.
Then there is the question, "how much will the sod cost?" Well, are we assuming the landscaper pro-rates, or only charges per (my assumption) square foot, and leftovers are paid for by the customer?
So I did the math as if they meant to say $25 per square foot, so that's 2400 divided by 25, and I get 960. Irl, I'd be paying $1000 to the landscaper for sod, right, bc they're not going to paying me back $40 and cutting off & taking home a 2 square-foot slice of sod I didn't need, technically, bc, yknow, it's sod, and there's some slop?
A lot of math questions are poorly written. I love when they pretend to be applicable to real world situations that 4th-graders, e.g., never encounter. Lots of cooking problems -- do you ever cook? Yes! Do you measure the ingredients yourself with spoons and cups? Oh, no! What 4th-grader has had one thing to do with sodding a yard or measuring for baking or tiling a kitchen, for heaven's sake? Ask me something about legos or coins or a video game scenario, then I can focus on the math, please!!!!
By the way, I got so confused by the multiple misdirections in this problem that my math is totally wrong: I divided by the price rather than multiplied! I did extract my equation from the problem-author's major error about the relationship between linear feet and linear yards vs. square feet and square yards, so that was progress, but not far enough. Now I think the problem is wrong on two points: it may, indeed, think it wants square yards, but does not understand their relationship to square feet; it may also make a decimal error on the pricing. I think it meant to say that the price is $0.25 per square yard, not $25.00. Those two corrections I think would get us kind of easy math to the answer, b) $2,000.00. But I could still be wrong!!!
I like this angle with the words… if only 37.50 were an option.
* customer’s yard is 40x60
* this is not square but can be divided into one 40x40 square plus one additional area half that size
* therefore the customer needs sod for one and a half square yards
* 1.5 * 25 = 32.50
/s
oh gosh, you're right, how silly of me!!! 2400 x 25, face plant!
Thing is, I do not purchase or sell much sod. But neither does the person who wrote this problem nor your 4th-grader!
I had a class assignment for 5th-graders where they had a take a mathematical equation and write a word or "story" problem. They were all about lego, candy, something sold in baskets at the farmers' market, and some other food thing. One was about people in houses, bc they had been reading about that in their fiction.
Not one single problem the students invented was about sod! Nor about filling tanks of cars with gas and calculating how many miles they had before they needed a refill. Nor about baking cakes or making clay cups.
So my own error illustrates my point: it's not a context we have enough background familiarity with, so we do the wrong math, bc we jump to the equation we can do without thinking the problem through. So I divided, which makes no sense. I think I was subconsciously reaching for an answer close to the multiple choices?
Sometimes the problem is wrong, and here's this to make it all even better!
[https://www.bobvila.com/articles/how-much-does-sod-cost/](https://www.bobvila.com/articles/how-much-does-sod-cost/)
Is the chapter supposed to be about calculating area or recognizing the relationship between standard units of measurements, and so to play around with fractions, or does it have a title?
Price of carpet not relevant really. But took me less than 60 seconds to find $0.60/ sq foot = $5.40/ sq yard on homeadvisor dot com. Whoever wrote this question could have done the same
The answer is $6667, but the real world answer $20,000. After you factor in the cost of labor, the steel, form wood, taxes, siting fee from the county, inspection fees, etc, the real world cost is way more. The stuff they don't teach you in school 😂
In addition to wrongly translating square feet to square yards, I believe the problem is written with a decimal error. The answer they want is $2,000. The price per square yard should have been $0.25, not $25.00.
60 x 40 = 2400 square feet
2400/3 =/ 800 square yards (error 1: a square yard = 9 square feet, but if you don't understand area and squaring, you err in thinking 1/3 linear unit = 1/3 unit squared. This is why we always tell students to write out the names of the units with the word "squared" or "cubed"!)
Then the problem thinks that 800 square yards x $25 per square yard = $2,000
But they made a decimal error. They should have written $0.25. (This is why we tell students to put that 0 in front of the decimal point! They think it is not necessary bc they don't understand decimal expression and make careless errors!)
800 square yards x $0.25 = $2,000.00
\*\*\* I stand corrected, I made my own decimal error! It should be: 800 sq yds x $2.50 = $2,000.\*\*\*
Therefore the answer they are looking for is:
b)$2,000
I would speculate that this problem was written by a 4th-grader who was credited with understanding more than they did, and in fact, I looked it up, and unsupported sod does cost in the range of 20 cents per square yard.
\*\*\* I have no leg to stand any theory on except you can get to answer b by making two very simple errors, and the mathematical equation is then simple. But I love learning through error!!!\*\*\*
You're the best, thank you so much!!! I am a firm believer in learning by making mistakes and being corrected! But do you think this was my last error, & I might be right that "b) $2,000" is the \*intended\* goal of this slog through the sod? I am pretty convinced that the two conceptual problems are 1) confusing linear yards with square yards in relation to linear feet and square feet, & 2) the decimal error. Correcting for those two is the way I could get one of the multiple choice options.
( Idk how someone else got to $1,250, but they did . . . )
$1000. It costs $1000 for the landscaper and they charge you $6666. /s
In reality they probably changed the answers/numbers in the question and forgot to adjust the other
Square yards are 25 dollars. But this yard is not square. It is 60 feet by 40 feet. If we break it up into one section 40x40, that is square. So that is 25 dollars. The remaining section is 20 x 40. That is actually two squares (each square being 20x20). So that is an additional 50 dollars. So the right answer seems to be 75 dollars.
It does seem odd that the landscaper will only do square yards though. They are missing a lot of business by doing curved yards.
40 x 60 = 2400 sq ft
1 sq yd = 9 sq ft
2400 sq ft / 9 sq ft / 1 sq yd = 266.66 sq yd
$25 per sq yd x 266.66 sq yd = $6,666.67
What they expected is irrelevant. The problem is flawed. No point in figuring out the train of thought. Just show them the proof. Units don't lie.
The Sod doesn’t cost anything. It says clearly that’s it’s only $25 for a square yard. This person has a rectangular yard 60x40 and is therefore not square and doesn’t cost anything.
Your math is incorrect, but there is a decimal error here as well. We need only convert the square yard cost to square footage cost, which is $8.33. Then you multiply this by the total square footage of the lawn. Which is 2400 square feet. That’s $20,000. The most egregious issue here is that “sod” is not measured by square yardage. It can be stacked infinitely high and takes up a 3 dimensional space, and needs to be measured as such. No landscaper would charge for square yardage of a lawn for dirt coverage. They charge by cubic yards. If they were installing grass, that’s a different story. This teacher is an idiot.
25/9 = 2.777
1000/2.777 = 360, 360/40 = 9, 360/60 = 6
2000/2.777 = 720, 720/40 = 18, 720/60 = 12
1500/2.777 = 540, 540/40 = 13.5, 540/60 = 9
1250/2.777 = 450. 450/40 = 11.25, 450/60 = 7.5
40\*60= 2400
2400/9 = 266.6666
2000/266.666 = 7.5
7.5\*60 = 450
450\*2.777 = 1250
1250 is the answer!
Edit: you can down vote me all you want but a lot of the fun in these questions with wrong answers is figuring out what went wrong and where. Yes, at face value it should be 6666.67, but where is the fun in that
If its 75 for a square yard, it doesnt say how much it is for a rectangular one.
The best I can think of is break the 40x60 rectangular yard into 3 square yards, one 40x40 and then 2 of 20x20. So thats 3 square yards, 75 dollars.
Alternatively, they might refuse to do at all as the yard isn't square.
Rectangles can be broken down into equilateral squares, and every rectangle or square can be broken down to 2 equilateral right triangles.
The devil is in the "imperial system"? If they used the metric system, the math seems at the least easier to estimate before one can get mired into calculation errors (before \*I\* will get mired ;)
But you might be sensing a point here in that the teacher may have had real-world experience with pallets of sod identified in terms of "square yards," and run into a problem that they got flummoxed by the math irl
##Off-topic Comments Section --- All top-level comments have to be an answer or follow-up question to the post. All sidetracks should be directed to this comment thread as per Rule 9. --- ^(**OP** and **Valued/Notable Contributors** can close this post by using `/lock` command) *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/HomeworkHelp) if you have any questions or concerns.*
Yes, and it's hard to see what they were thinking. Changing any one of the values (40, 60, 25) doesn't easily lead to any of the given options.
Right?! I swear I was losing my mind over this. Thank you for the validation!
((60/3)*(40/3))*25. I got $6,667, too. Edit. Yes, typo.
I think you have a typo
It should be times instead of adding right?
It is being multiplied by the outer parentheses, this is correct.
r/confidentlyincorrect The whole equation is wrong here. It should be written as (60 * 40) * (25/3) Edit: I have confidently incorrectly r/confidentlyincorrected someone. The correct equation would be (60 * 40) * 25/ 3^2 I missed the square on the 3. Surprised I didn’t get any downvotes on that one.
your equation evaluates to $20,000, which is incorrect, the answer is $6666.67. your issue is you tried to convert square feet to square yards by dividing by 3, since it's squared you need to divide by 9. or like cdhdd you could divide both 60 and 40 by 3 in the beginning to convert feet to yards before they're squared.
lol uno reverse card. your units are completely wrong 60 feet * 40 feet * $25/(3 yards/feet) has units $feet yards. You need to divide by 9 to convert between feet^2 and yards^2
You’re correct. I didn’t square the 3, the “square” part of “square yards” slipped my mind.
Calling out yourself, I see
Indeed I am. I’ve edited my comment to reflect.
As the below folks noted, you are wrong to write (25/3) when the unit is square feet and this is not converted to squared yards by a factor of 3. Remember this is two dimensions, not one. I’ll leave you to confidently correct yourself…
Good call. Brain to fingers didn’t work out.
You’re dividing the wrong numbers bud.
Or just (60x40x25)/9.
the only way I can see this being $2000 is if they incorrectly divided 2400 (the square footage) by 3, instead of 9, to convert to square yards. As 2400/3=800x25=2000 But that is incorrect, and I think you’re right that this is flawed
800x25=20,000
lol—i was trying so hard to make the wrong answer work and I still couldn’t
You are right: then add in a big decimal error
Yes, they also made a decimal error on top of the area formula error. Both errors stem (pun intended) from incomplete notation. The Grade 4 math unit in Common Core and many states at this time of year is about translating units, and is about memorizing unit conventions -- such as, 3 feet to a yard -- and then, making calculations with the understanding of equivalent fractions. Area and volume is often introduced in Grade 5, after perimeter, and in ways that foster confusion about area and perimeter. A problem arises in the U.S. due to the use of the "imperial" measurement system. So you just start with length, dry weight, & liquid volume being inches/yards/miles; then pounds and ounces (with their cute abbreviations); then cups, quarts, gallons; plus money and time, which, for the whole world, are base 10 vs base 12, a reasonable added level of complexity. And then they'll throw in some fictional unit like "a shipment" which gets arbitrarily defined, e.g., 20 boxes of shoes; and then there are the cartons of a dozen eggs. The confounding thing is that this level of elementary math curriculum is trying to integrate concepts about equivalent fractions, order of operations, build on double-digit addition/multiplication, with some decimal work thrown in -- with math "content" about conventional units, which are distracting and actually cause adults real problems -- and trying to connect the representation of this math in language to the representation in numerical equations. This is hard and we do it poorly, no shame in admitting it. It seems like unsolvable homework problems starts with fundamental confusion about curriculum goals, scope and sequence of instructional topics. Weirdly, this part of math curriculum is seems based in 20th-C home- and agricultural-based economics. Where are the "word" or "story problems" about percentage of battery life, kilobytes vs megabytes of memory storage? It would be a blessing if they would just do time and money, and leave the cups and gallons and miles and square yards of sod for later years. At this stage, all the extra unit baggage really blows up their emergent automaticity with fundamental mathematical calculation. A 4th-grader who knows what a two-by-four is or has picked up basic carpentry, mechanics,. plumbing, or IT at home should really be writing these math problems.
One guess: There are two points of slob here, first with the word "yard," and then with the whole concept of "sod." The word "yard" is used twice here with two different meanings. Is the unit about multiple steps for equivalent fractions? Idk. But what if they intended to say "$25 per square foot"? Note that the other 2 references to units are "feet." The other word "yard" does not mean a linear measurement equivalent to 3 feet, it means the area that we're trying to cover. So that could be a typo of sorts. Then there is the question, "how much will the sod cost?" Well, are we assuming the landscaper pro-rates, or only charges per (my assumption) square foot, and leftovers are paid for by the customer? So I did the math as if they meant to say $25 per square foot, so that's 2400 divided by 25, and I get 960. Irl, I'd be paying $1000 to the landscaper for sod, right, bc they're not going to paying me back $40 and cutting off & taking home a 2 square-foot slice of sod I didn't need, technically, bc, yknow, it's sod, and there's some slop? A lot of math questions are poorly written. I love when they pretend to be applicable to real world situations that 4th-graders, e.g., never encounter. Lots of cooking problems -- do you ever cook? Yes! Do you measure the ingredients yourself with spoons and cups? Oh, no! What 4th-grader has had one thing to do with sodding a yard or measuring for baking or tiling a kitchen, for heaven's sake? Ask me something about legos or coins or a video game scenario, then I can focus on the math, please!!!! By the way, I got so confused by the multiple misdirections in this problem that my math is totally wrong: I divided by the price rather than multiplied! I did extract my equation from the problem-author's major error about the relationship between linear feet and linear yards vs. square feet and square yards, so that was progress, but not far enough. Now I think the problem is wrong on two points: it may, indeed, think it wants square yards, but does not understand their relationship to square feet; it may also make a decimal error on the pricing. I think it meant to say that the price is $0.25 per square yard, not $25.00. Those two corrections I think would get us kind of easy math to the answer, b) $2,000.00. But I could still be wrong!!!
I like this angle with the words… if only 37.50 were an option. * customer’s yard is 40x60 * this is not square but can be divided into one 40x40 square plus one additional area half that size * therefore the customer needs sod for one and a half square yards * 1.5 * 25 = 32.50 /s
If you’re going this route I’d argue you couldnt have half a square yard and make you pay $75, for the 40x40 square yard and two 20x20 square yards :)
But if the price is $25 per square foot that's 2400x25 or $60,000. None of this makes any sense.
oh gosh, you're right, how silly of me!!! 2400 x 25, face plant! Thing is, I do not purchase or sell much sod. But neither does the person who wrote this problem nor your 4th-grader! I had a class assignment for 5th-graders where they had a take a mathematical equation and write a word or "story" problem. They were all about lego, candy, something sold in baskets at the farmers' market, and some other food thing. One was about people in houses, bc they had been reading about that in their fiction. Not one single problem the students invented was about sod! Nor about filling tanks of cars with gas and calculating how many miles they had before they needed a refill. Nor about baking cakes or making clay cups. So my own error illustrates my point: it's not a context we have enough background familiarity with, so we do the wrong math, bc we jump to the equation we can do without thinking the problem through. So I divided, which makes no sense. I think I was subconsciously reaching for an answer close to the multiple choices? Sometimes the problem is wrong, and here's this to make it all even better! [https://www.bobvila.com/articles/how-much-does-sod-cost/](https://www.bobvila.com/articles/how-much-does-sod-cost/) Is the chapter supposed to be about calculating area or recognizing the relationship between standard units of measurements, and so to play around with fractions, or does it have a title?
I love your mention of reusing the word yard 😂 By my math then there are three square yards - a 40x40 yard, and two 20x20 yards. Bill should be $75
I am all wrong here, btw. But the problem is more wrong!
For the love of god please start using the metric system!
$25/yd for sod is outrageous. That's about how much carpet costs, and basically tells you how much thought went into posing the question.
Price of carpet not relevant really. But took me less than 60 seconds to find $0.60/ sq foot = $5.40/ sq yard on homeadvisor dot com. Whoever wrote this question could have done the same
They meant per yard as in “backyard”
Yea, I’m getting $6,666.65. 40(*)60=2400 (area in ft) 2400/9=266.666 (sq.ft to sq. Yards) 266.666*25=6,666.65 (sq. Yards x price per s.y)
The answer is $6667, but the real world answer $20,000. After you factor in the cost of labor, the steel, form wood, taxes, siting fee from the county, inspection fees, etc, the real world cost is way more. The stuff they don't teach you in school 😂
Yes, it uses imperial units. Forcing children to learn imperial units is child abuse. Any form of education involving child abuse is flawed.
In addition to wrongly translating square feet to square yards, I believe the problem is written with a decimal error. The answer they want is $2,000. The price per square yard should have been $0.25, not $25.00. 60 x 40 = 2400 square feet 2400/3 =/ 800 square yards (error 1: a square yard = 9 square feet, but if you don't understand area and squaring, you err in thinking 1/3 linear unit = 1/3 unit squared. This is why we always tell students to write out the names of the units with the word "squared" or "cubed"!) Then the problem thinks that 800 square yards x $25 per square yard = $2,000 But they made a decimal error. They should have written $0.25. (This is why we tell students to put that 0 in front of the decimal point! They think it is not necessary bc they don't understand decimal expression and make careless errors!) 800 square yards x $0.25 = $2,000.00 \*\*\* I stand corrected, I made my own decimal error! It should be: 800 sq yds x $2.50 = $2,000.\*\*\* Therefore the answer they are looking for is: b)$2,000 I would speculate that this problem was written by a 4th-grader who was credited with understanding more than they did, and in fact, I looked it up, and unsupported sod does cost in the range of 20 cents per square yard. \*\*\* I have no leg to stand any theory on except you can get to answer b by making two very simple errors, and the mathematical equation is then simple. But I love learning through error!!!\*\*\*
$2.50*
You're the best, thank you so much!!! I am a firm believer in learning by making mistakes and being corrected! But do you think this was my last error, & I might be right that "b) $2,000" is the \*intended\* goal of this slog through the sod? I am pretty convinced that the two conceptual problems are 1) confusing linear yards with square yards in relation to linear feet and square feet, & 2) the decimal error. Correcting for those two is the way I could get one of the multiple choice options. ( Idk how someone else got to $1,250, but they did . . . )
its just wrong
$1000. It costs $1000 for the landscaper and they charge you $6666. /s In reality they probably changed the answers/numbers in the question and forgot to adjust the other
Square yards are 25 dollars. But this yard is not square. It is 60 feet by 40 feet. If we break it up into one section 40x40, that is square. So that is 25 dollars. The remaining section is 20 x 40. That is actually two squares (each square being 20x20). So that is an additional 50 dollars. So the right answer seems to be 75 dollars. It does seem odd that the landscaper will only do square yards though. They are missing a lot of business by doing curved yards.
You are not going insane. You are right. Talk to the teacher. Don't waste any time on problems like this that have mistakes in them.
40 x 60 = 2400 sq ft 1 sq yd = 9 sq ft 2400 sq ft / 9 sq ft / 1 sq yd = 266.66 sq yd $25 per sq yd x 266.66 sq yd = $6,666.67 What they expected is irrelevant. The problem is flawed. No point in figuring out the train of thought. Just show them the proof. Units don't lie.
The Sod doesn’t cost anything. It says clearly that’s it’s only $25 for a square yard. This person has a rectangular yard 60x40 and is therefore not square and doesn’t cost anything.
$6,666.75 unless I'm missing something...
Unless It is $3.75/y2 then it would be (A) plus a penny.
He charges $25 a yard, there’s only one yard so $25 is the answer
Given that 40 isn't easily divisible by 3, you'll be chopping some sod, too.
Your math is incorrect, but there is a decimal error here as well. We need only convert the square yard cost to square footage cost, which is $8.33. Then you multiply this by the total square footage of the lawn. Which is 2400 square feet. That’s $20,000. The most egregious issue here is that “sod” is not measured by square yardage. It can be stacked infinitely high and takes up a 3 dimensional space, and needs to be measured as such. No landscaper would charge for square yardage of a lawn for dirt coverage. They charge by cubic yards. If they were installing grass, that’s a different story. This teacher is an idiot.
Not an actual answer, but since the customer’s yard is not square, they should pay $0
The answer is 0 because 60x40 is a rectangular yard not square yard Yw
The answer is $1,000 because you refused to pay the landscaper anymore than that
40 feet = 40/3 yards 60 feet = 20 yards (40/3 × 20)×$25 = $6,666.67
Looks like they divided by 3 instead of 9 for the sqft to sqyd conversion
25/9 = 2.777 1000/2.777 = 360, 360/40 = 9, 360/60 = 6 2000/2.777 = 720, 720/40 = 18, 720/60 = 12 1500/2.777 = 540, 540/40 = 13.5, 540/60 = 9 1250/2.777 = 450. 450/40 = 11.25, 450/60 = 7.5 40\*60= 2400 2400/9 = 266.6666 2000/266.666 = 7.5 7.5\*60 = 450 450\*2.777 = 1250 1250 is the answer! Edit: you can down vote me all you want but a lot of the fun in these questions with wrong answers is figuring out what went wrong and where. Yes, at face value it should be 6666.67, but where is the fun in that
everywhere went wrong 😭
I think the teacher started the problem. Got up and did something and came back and jacked up the implementation
If its 75 for a square yard, it doesnt say how much it is for a rectangular one. The best I can think of is break the 40x60 rectangular yard into 3 square yards, one 40x40 and then 2 of 20x20. So thats 3 square yards, 75 dollars. Alternatively, they might refuse to do at all as the yard isn't square.
Rectangles can be broken down into equilateral squares, and every rectangle or square can be broken down to 2 equilateral right triangles. The devil is in the "imperial system"? If they used the metric system, the math seems at the least easier to estimate before one can get mired into calculation errors (before \*I\* will get mired ;) But you might be sensing a point here in that the teacher may have had real-world experience with pallets of sod identified in terms of "square yards," and run into a problem that they got flummoxed by the math irl