Question

Suppose that m varies inversely as the cube of n.
When n = 4, m = 0.25. Find m when n = 2.

Answer 1

In general when y varies inversely as x,

y = k/x or xy = k

In this case, m varies inversely as the cube of n, therefore,
m = k/n^3 or n^3m = k

since n = 4 and m = 0.25, we substitute that into the equation to get

4^3 * .25 = k, then solve for k:
64*.25 = k
16 = k

Do you believe you can find m when n = 2 now?