From the information given, the basketball player makes 6 out of 10 free throws. This means that the probability that she will make a throw from a number of free throws is
6/10 = 3/5
Recall, total probability is 1
The probability that she will not make a throw from a number of free throws is
1 - 3/5 = 2/5
Thus, if she has 35 free throws, the number of throws that she will not make is
2/5 x 35
= 14
She will not make 14 throws