Simple math problem

[the prodogy]

Ok, so I'm having a problem with a simple math concept.

1 m = 100 cm

Now I'm given 5 m. Lets say for a simple equation it says "answer = (length)^2. All the answers are in cm.

So if I square 5, I get 25 m, which equals: "25,000 cm"

BUT, if I convert 5 m into cm, I get 500 cm. 500 cm squared equals: "250,000 cm"

Why are these answers different?

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[ksmi117]

Ok, so I'm having a problem with a simple math concept.

1 m = 100 cm

Now I'm given 5 m. Lets say for a simple equation it says "answer = (length)^2. All the answers are in cm.

So if I square 5, I get 25 m, which equals: "25,000 cm"

BUT, if I convert 5 m into cm, I get 500 cm. 500 cm squared equals: "250,000 cm"

Why are these answers different?

You're problem is in the first half. You tried to convert 25m^2 to cm^2 using the m to cm conversion.

Yes 100 cm = 1 m, but (100 cm)^2 = (1 m)^2. So 10,000 cm^2 = 1m^2.

In the first part you are going from 25 m^2 to cm^2, so you'd get 250,000 cm^2.

Make sense? I feel like I didn't explain well. Tell me if I didn't.

 

[LostInStudy]

You're problem is in the first half. You tried to convert 25m^2 to cm^2 using the m to cm conversion.

Yes 100 cm = 1 m, but (100 cm)^2 = (1 m)^2. So 10,000 cm^2 = 1m^2.

In the first part you are going from 25 m^2 to cm^2, so you'd get 250,000 cm^2.

Make sense? I feel like I didn't explain well. Tell me if I didn't.

I don't see how that could have been explained more simply.
OP just remember to put everything in parenthesis like ksmi did. It helps keep your order of operations straight.

-LIS

 

[redlight]

Ok, so I'm having a problem with a simple math concept.

1 m = 100 cm

Now I'm given 5 m. Lets say for a simple equation it says "answer = (length)^2. All the answers are in cm.

So if I square 5, I get 25 m, which equals: "25,000 cm"

BUT, if I convert 5 m into cm, I get 500 cm. 500 cm squared equals: "250,000 cm"

Why are these answers different?

write out your units.

your first and second method have different units.

EDIT: as in the way you wrote it, you converted 25m^2 to 25,000 cm (haha somehow) whereas you should have converted to cm^2. method 2's units are cm^2.

 

[LostInStudy]

This is where using Scientific notation gets you out of any trouble you may have. Use it as often as possible.

-LIS

 

[redlight]

This is where using Scientific notation gets you out of any trouble you may have. Use it as often as possible.

-LIS

do you mean dimensional analysis?

the problem was OP did not keep track of units. the actual multiplication was right but the units did not match up.

 

[LostInStudy]

Both because he converted 25m to cm wrong also. If 1 m = 100 cm then 25 m equals 2500 cm. I'm not sure how the heck he got 25,000.

-LIS