Which is the initial value that shrinks an exponential growth function by 50%?

1/5

1/4

1/3

1/2

Suppose that the exponential growth function is y = 4^x.

If x = 1, then y = 4^1 = 4.

If x = 3, then y = 4^3 = 64.

Let the initial value be 1/2.

The growth function is now y = 1/2 * 4^x.

If x = 1, then y = 2 which is half of the y value before adding the 1/2.

If x = 3, then y = 1/2 * 64 = 32.

Answer: 1/2