If Y varies inversely as the cube root of x. If y = 4 when x = 27, how do you find y when x = 8?

1 Answer
May 17, 2017

y = 6 when x = 8

Explanation:

If y varies inversely as the cube root of x then we can express this algebraically thus

y = k*1/x^(1/3)

Using the values y = 4 when x = 27

We get 4 = k / 27^(1/3 )
4 = k /3

Therefore k = 12

The relationship can now be fully expressed as y = 12/x^(1/3 )

Using this rule when x = 8

y = 12 / 8^(1/3) = 12/2 = 6