help with math

• Xelement

  20 Oct 09, 20:27

  given that 960 / 5m is a perfect cube, find the smallest value of m.

   

  thanks

• qdtimes2

  20 Oct 09, 21:05

  if im not wrong, m = 3

  960 / 5m = 192 / m

  192 = 2 x 2 x 2 x 2 x 2 x 2 x 3

          = 4 x 4 x 4 x 3

  a cube has equal sides throughout, or it's three factors must be equal. in order for 192 / m to be a cube, at least the factor 3 must be removed.

  so m = 3

   

   

• Xelement

  20 Oct 09, 21:08

  Originally posted by qdtimes2:

  if im not wrong, m = 3

  960 / 5m = 192 / m

  192 = 2 x 2 x 2 x 2 x 2 x 2 x 3

          = 4 x 4 x 4 x 3

  a cube has equal sides throughout, or it's three factors must be equal. in order for 192 / m to be a cube, at least the factor 3 must be removed.

  so m = 3

   

   

  thanks thanks