In 1971 there were 294,105 females participating in high school sports. since then that number has increased by 8.5% per year. estimate the number participating in 2015. round to the nearest whole number.

First we have to calculate how many years passed: 2015 - 1971 = 44 years.
So n = 44 and 8,5% = 0,085 so r = 1 + 0.085 = 1.085.
The starting population is 294,105 and the formula is:
y = 294,105 * r^n = 294,105 * 1.085^44 =
= 294,105 * 36.21666 = 10,651,502.85 ≈ 10,651,503
In 2015 there were 10,651,503 females participating in high school sports.