Question

Y is inversely proportional to the cube of x. If Y = 3 when x = 2, find Y, when x is 3. Write a proportion. Solve for y. Show work.

Answer 1

"Y is inversely proportional to the cube of x" translates to Y = kx³ where k is unknown constant. We need to solve for k.

So we have Y = 3 and x = 2. Plug in and we get 3 = k2³ = 8k

So k = 3/8

Now we can solve for Y when x = 3

Y = (3/8)3³ = (3/8)27 = 81 / 8

Final answer: 81 / 8