Question

Z varies directly with X squared and inversely with Y. When X equals two and Y equals four, Z equals three. What is the value of Z when X equals four and Y equals nine

A: 2/3

B: 16/3

C: 8/3

D: 24

Answer 1

B

Explanation:

Set up the equation

z =
`(kx^2)/(y)`

Plug in the numbers to find the value of k

3 =
`(k(2^2))/(4)`

12 = 4k

3 = k

Solve to find the value of z

z =
`(3(4^2))/(9)`

z =
`(3(16))/(9)`

z = 48/9

z = 16/3