9514 1404 393
Answer:
37/45 ≈ 0.822
Explanation:
The formula for an exponential relation is ...
y = a·b^x
This question is asking for the value of b. It can be found by substituting the given values of x and y, and taking the ratio of the resulting equations.
90 = a·b^15
74 = a·b^16
Dividing the second equation by the first, we have ...
74/90 = (a·b^16)/(a·b^15)
74/90 = b
The decay factor is 74/90 = 37/45 ≈ 0.822