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#1
06-25-2000, 02:08 AM
 evilbeth Guest Join Date: Aug 1999
HELP!!!

(I feel so stupid!)

This is utterly embarassing but I am completely stupid when it comes to math, especially word problems and the like. No, really. Can someone help me with this seemingly simple math problem? It is not a homework question nor is it a trick question--I am just horrible at math and cannot figure this out to save my life!

Basically, all I need to know is how to find the volume (in cubic yards) of an area that is given in square miles by yards. In other words, I have a word problem that says an enclosure is an area 10 miles square by 10 yards deep and I need to know the volume.

Please do not taunt me mercilessly--just help! This mathaphobia is a real disease!
#2
06-25-2000, 02:24 AM
 Nanook of the North Shore Guest Join Date: Jun 2000
Convert either the yards to miles or the miles to yards depending on what you need for the final answer. Then its a simple volume calculation.
#3
06-25-2000, 02:26 AM
 Bill H. Guest Join Date: Jun 2000
Bear in mind that it's really 10 miles by 1 mile by 10 yards, so you'll need to convert the 10 miles to yards, and the 1 mile to yards. Then multiply the three together for the answer. (note that 10 mi x 1 mi isn't the only way of reflecting 10 sq miles, but any way you cut that part will get you the same answer.)
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#4
06-25-2000, 02:29 AM
 BigGiantHead Guest Join Date: Sep 1999
Yeah, 10 miles (on each side) is 17,600 yards.

Multiply that by 17,600 yards again for an area of 309,760,000 square yards.

Multiply by height of 10 yards for 3,097,600,000 cubic yds.

Egads, that's a lot!
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#5
06-25-2000, 02:36 AM
 sailor Guest Join Date: Mar 2000
Bill you are assuming 10 sq mi but she said 10 miles square which would be 100 square miles
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#6
06-25-2000, 02:40 AM
 Mauve Dog Guest Join Date: Apr 2000
Quote:
 HELP!!! (I feel so stupid!) This is utterly embarassing but I am completely stupid when it comes to math, especially word problems and the like. No, really. Can someone help me with this seemingly simple math problem? It is not a homework question nor is it a trick question--I am just horrible at math and cannot figure this out to save my life! Basically, all I need to know is how to find the volume (in cubic yards) of an area that is given in square miles by yards. In other words, I have a word problem that says an enclosure is an area 10 miles square by 10 yards deep and I need to know the volume. Please do not taunt me mercilessly--just help! This mathaphobia is a real disease!
Step one: Convert everything to the same units. If you want the answer in yd^3, then the first thing we need to do is convert the miles to yards. Simple enough:

1 mile = 5280ft = 1760 yds.

10 miles, then, is 17,600 yards (1760 x 10)

Step two: Restate the problem with the new units. Now, the problem is this: The enclosure is an area 17,600 yards square by 10 yards deep.

Step three: Crank it out

The volume is simply the area x depth, so all we need to do is this:

17,600 yds x 17,600 yds x 10 yds

Or,

3.1 x 10 ^ 9 cubic yards (The actual answer is 3,097,600,000 yd^3).

But wait... I just re-read you post. And now I am confused

First you say the area is given in square miles, then you say the area is 10 miles square. Those mean two different things (at least to me)! An area of 10 miles square implies that each side is 10 miles long (meaning the area is actually 100 square miles - and the above is the answer). If the area is actually 10 square miles, that's a bit different:

(10 mi^2) x (1760 yds / 1 mi)^2 = (10 mi^2) x (3,097,600 yd^2 / 1 mi^2) = 30,970,600 yd^2

So, 10 square miles is 30,970,600 square yards.

To get the volume, we simply multiply this by the 10-yard depth:

30,970,600 yd^2 x 10 yd = 309,706,000 yd^3

As you can see, this answer is 100x less than the previous answer.

Anyway, my guess is that you meant the area you are starting with is 10 square miles, so the second answer is the correct one.

Sorry for such a lengthy response to your question.
#7
06-25-2000, 02:40 AM
 evilbeth Guest Join Date: Aug 1999
So, working with a number not so simple as 10, say, 32, I would just convert 4 feet to yards and 8 feet to yards and multiply it out as L X W X H?

Or not?
#8
06-25-2000, 02:41 AM
 Mauve Dog Guest Join Date: Apr 2000
Heh heh...four people responded in the time it took me to write my reply, too. I guess Im just entirely too long-winded
#9
06-25-2000, 02:43 AM
 Mauve Dog Guest Join Date: Apr 2000
Quote:
 So, working with a number not so simple as 10, say, 32, I would just convert 4 feet to yards and 8 feet to yards and multiply it out as L X W X H? Or not?
Assuming that the area is 4' x 8' and you wanted the answer in yards, yes. That's all you'd need to do
#10
06-25-2000, 02:44 AM
 evilbeth Guest Join Date: Aug 1999
We simul-posted. The question says "an area 32 miles square by 10 yards deep." Sorry about the confusion--I told you I cannot do math!
#11
06-25-2000, 02:49 AM
 Mauve Dog Guest Join Date: Apr 2000
Quote:
 We simul-posted. The question says "an area 32 miles square by 10 yards deep." Sorry about the confusion--I told you I cannot do math!
32 miles square (again, assuming this really means 32 square miles) would be converted to yards the same way. You can treat it as an 8 mi x 4 mi enclosure, convert everything to yards, then multiply everything together:

(8 mi x (1760 yd / mi)) x (4 mi x (1760 yd / mi)) x 10 yd = ...
#12
06-25-2000, 02:55 AM
 evilbeth Guest Join Date: Aug 1999
Thank you all so much! You completely saved my life in 41 minutes flat!
#13
06-25-2000, 03:00 AM
 RM Mentock Guest Join Date: Mar 1999
Quote:
 MauveDog wrote: As you can see, this answer is 100x less than the previous answer.
10x, not 100x. You put the 6 in the wrong place.

32 miles square surely means 32 miles by 32 miles. If it said 32 square miles, then it would be 32 miles by 1 mile, or even 8 miles by 4 miles.
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#14
06-25-2000, 03:14 AM
 evilbeth Guest Join Date: Aug 1999
OK, so is it 32(X 1760) times 32(X 1760) times 10 or is it 4(X 1760) times 8(x 1760) times 10???
#15
06-25-2000, 03:16 AM
 Mauve Dog Guest Join Date: Apr 2000
Quote:

Quote:
 MauveDog wrote: As you can see, this answer is 100x less than the previous answer.
10x, not 100x. You put the 6 in the wrong place.

32 miles square surely means 32 miles by 32 miles. If it said 32 square miles, then it would be 32 miles by 1 mile, or even 8 miles by 4 miles.
I did indeed put the 6 in the wrong place. Oops. The correct answer was 309,760,000 yd^3. Which is, of course, only 10x less than the previous answer.

And, as I indicated, I would interpret '32 miles square' the same way. But I wasn't entirely sure whether evilbeth meant '32 square miles' or '32 miles square'.
#16
06-25-2000, 03:18 AM
 Mauve Dog Guest Join Date: Apr 2000
Quote:
 OK, so is it 32(X 1760) times 32(X 1760) times 10 or is it 4(X 1760) times 8(x 1760) times 10???
It would be either:

32 x (1760 x 1760) x 10

or:

(8 x 1760) x (4 x 1760) x 10
#17
06-25-2000, 03:22 AM
 Mauve Dog Guest Join Date: Apr 2000
Unless, of course...

The enclosed area is 32 miles on each side, in which case it would be:

(32 x 1760) x (32 x 1760) x 10
#18
06-25-2000, 03:46 AM
 evilbeth Guest Join Date: Aug 1999
AACCCKKKK! Do I just pick the one that I like since the word problem didn't give me specifics? Or should I just do it both ways and indicate that the confusion is on the part of the problem-writer?
#19
06-25-2000, 03:58 AM
 Mauve Dog Guest Join Date: Apr 2000
Quote:
 AACCCKKKK! Do I just pick the one that I like since the word problem didn't give me specifics? Or should I just do it both ways and indicate that the confusion is on the part of the problem-writer?
Personally, I'd give both answers and indicate the confusion.
#20
06-25-2000, 04:09 AM
 evilbeth Guest Join Date: Aug 1999
OK, thanks a million!

Oh, and thanks for not calling me names or indicating how hard you were laughing at me!
#21
06-25-2000, 04:32 AM
 Mauve Dog Guest Join Date: Apr 2000
Quote:
 OK, thanks a million! Oh, and thanks for not calling me names or indicating how hard you were laughing at me!
I would never even think of doing such a thing
#22
06-25-2000, 11:43 AM
 Eggs à la Ted Guest Join Date: Jun 2000
Quote:
 (10 mi^2) x (1760 yds / 1 mi)^2 = (10 mi^2) x (3,097,600 yd^2 / 1 mi^2) = 30,970,600 yd^2
Sometimes I just love the metric system.
#23
06-25-2000, 11:55 AM
 RM Mentock Guest Join Date: Mar 1999
Quote:
 AACCCKKKK! Do I just pick the one that I like since the word problem didn't give me specifics? Or should I just do it both ways and indicate that the confusion is on the part of the problem-writer?
If the problem actually states "an area 32 miles square by 10 yards deep," (which I think you say it does) then there is no confusion on the part of the problem. It does mean an area 32 miles by 32 miles. That should be your answer.
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