Where art thou Math genius?

Question

In when figuring the volume of a rectangular prism with the dimesions of 20mm, 20mm and 20mm, you would get 8000mm but when you convert it to cm, you would get 800cm. However if you convert 20mm, 20mm and 20mm to 2cm, 2cm and 2cm then you would have 8cm and 800mm? Why is that? And which is right?

Answer 1

gotta have the right units. Volume means we're dealing with cubic units.

20 mm * 20mm * 20mm = 8000 mm^3
8000 mm^3 is NOT 800 cm^3... since they're cubic mmm.
We would have to convert like so

8000 mm^3 * (1 cm/10mm)*(1cm/10mm)*(1cm/10mm) =
8 cm^3

(1 cubic centimeter is a rectangular prism with sides 10 mm... so we can put 1000 cubic millimeters in 1 cubic centimeter)

1 mm is not the same as 1 mm^3

Hope this helps.

Answer 2

You're forgetting that 20mm x 20mm x 20mm is 8000 *cubic* millimeters, not 8000 millimeters. The conversion from cubic millimeters to cubic centimeters is not 10, but rather 10 for each of the 3 dimensions, so 10 x 10 x 10, or 1000.

Answer 3

The conversion from cubic centimeters to cubic mm is multiplying and dividing by 1000 - so 8 cubic CM and 8000 cubic MM are the same

Answer 4

mm : 20*20*20 = 8000 (mm)^3
cm : 2 * 2 * 2 = 8 (cm)^3

they are both right ...just using different measures
if linear measure changes by 10, area changes by 100 and volume changes by 1000.

just imagine a cubic container and fill it with cubic boxes
10*10*10layers =1000 ... its the same thing.

Answer 5

(20 mm) x (20 mm) x (20 mm) = 8000 cubic mm.

(2 cm) x (2 cm) x (2 cm) = 8 cubic cm.

Since cubic cm are not cm, and cubic mm are not mm, the conversion factor is NOT 10, it's 10x10x10 = 1000.

Answer 6

ok i guess its a square of 20*20*20