from 2007 equations, ineq, & vics...if the scale model....

[NathanielJ.Ho]

If the scale model of a cube sculpture if .5 cm per every 1 m of the real sculpture, what is the volume of the model, if the volume of the real sculpture is 64 m^3.

This is a very easy problem but for some reason I can't get it to work if i convert .5 cm to meters.

.5 cm = .005 m

I know that because the volume of the cube is 64, then each side is 4 m.

Then I set up .005 m/1 m = x m/4 m
Cross multiply and I get .005m(4m) = x
x = .02 meters

That means one side is .02 meters. V = .02(.02)(.02) = .000008 m, which (multiply by 100) is .0008 centimeters.

The real answer is 8 cm. The solution in the book says you should just set up the ratio 5 cm/1 m = x cm/4m. My question is, why can't I convert to centimeters to meters first?

[mikhsor]

If the scale model of a cube sculpture if .5 cm per every 1 m of the real sculpture, what is the volume of the model, if the volume of the real sculpture is 64 m^3.

This is a very easy problem but for some reason I can't get it to work if i convert .5 cm to meters.

.5 cm = .005 m

I know that because the volume of the cube is 64, then each side is 4 m.

Then I set up .005 m/1 m = x m/4 m
Cross multiply and I get .005m(4m) = x
x = .02 meters

That means one side is .02 meters. V = .02(.02)(.02) = .000008 m, which (multiply by 100) is .0008 centimeters.

The real answer is 8 cm. The solution in the book says you should just set up the ratio 5 cm/1 m = x cm/4m. My question is, why can't I convert to centimeters to meters first?

Your solution is ok. Don't forget that you get m^3 not just m (because you multiply .02m*.02m*.02m= .000008(m^3). Therefore you have to then multiply by 100^3 and you will get 8 cm^3

[Ben Ku]

That means one side is .02 meters. V = .02(.02)(.02) = .000008 m, which (multiply by 100) is .0008 centimeters.

When you calculate the volume
V = (0.02 m)(0.02 m)(0.02 m) = 0.000008 m^3 (cubic meters!). Remember that 1 cubic meter is NOT 100 cubic centimeters. (In fact, 1 cubic meter = (100 cm)(100 cm)(100 cm) = 1,000,000 cubic centimeters)

You can instead use 2 cm instead of 0.02 m. So now, V = (2 cm)(2 cm)(2 cm) = 8 cm^3.

Hope this makes sense.