Question

Shea made 11 of her first 17 free-throw attempts. What is the minimum number of her next 20 free-throw attempts that she must make for her overall success rate to be at least $80\%$? Express your answer to the nearest whole number.

Answer 1

19 throws.

Explanation:

For her success rate to be 80% in 37 throws she must make 0.8 * 37

= 29.6 throw - that is 30 to nearest throw.

So for the next 20 throws she must make 30 - 11 = 19 throws.