It's the same as multiplying by 1/3 surely?

This is correct. No idea why there is so much spam here (I'm not a fan of him either, but keep personal things out of HW helpline).

It is one of the "laws" or "axioms" of algebra that a/b = a*(1/b)

In other words, division is actually defined in advanced mathematics as multiplication by the reciprocal (yes, I had to look up the spelling).

Example: 5*(1/5) = 1

8*(1/8) = 1

In general, it is assumed that every (NON-ZERO) number has what we call a "multiplicative inverse" that brings it to 1 when multiplied by it.

This multiplicative inverse is nothing more than 1/(whatever number)

Example: 3*(1/3) = 1 because (1/3) is the "reciprocal" of 3.

This post was edited by Casey on Jul 8 2014 06:25pm