Please help me answer 2 algebra probability questions?

Question

1. Carter High divides students into advisory classes by a group of teachers. The table shows the number of students in each class.
Class Number of Students
Alexander 34
Garza 28
Jones 36
Kelley 27
Tesco 35
Total 160

The principal uses a computer to randomly select the name of a student from all the students in the advisory classes. With the computer program, it is possible to draw the name of the same student twice. If the principal selects the name of a student from the Jones class on the first try, what is the probability she will draw the name of another student from the Jones class on the second try? Give your answer as a simplified fraction.

2. The probability that a dessert sold at a certain café contains strawberries is 26%. The probability that a dessert contains both strawberries and whipped topping is 18%. Find the probability that a randomly chosen strawberry dessert contains whipped topping. Round to the nearest tenth of a percent. Thank you so much

Answer 1

1> Since the first student is not to be picked on the second try, the probability is 35/160 = 7/32.

 

2> P(A|B) = P(A and B)/P(B)

      In this case .18/.26 = 69.2%