Question

What is the rate of decay? 

y = 200(0.85)^4

Answer 1

The rate of decay is found by looking at the exponent of the decay factor. In this case, the decay factor is 0.85, and the exponent is 4. Therefore, the rate of decay is 4.

Answer 2

85%
85%

0.15%
0.15%

15%
15%

0.85%

Answer 3

The correct answer is 15%. The exponent of 4 in y = 200(0.85)^4 represents the number of times the decay factor is multiplied by itself, so the rate of decay is 15% for each iteration.