2.) A bookshelf contains seven math textbooks and three science
textbooks. If two textbooks are drawn at random without replacement,
what is the probability both books are science textbooks? *
A)1/15
B)3/10
C)3/7
D)1/2

A

Step-by-step explanation:

the probability of the first book being science is (science books/total books)

there are 3 science books and 7 + 3 = 10 total books

so the probability the first time is 3/10

if you pick a science book the first time and don't replace it, the number of science books drops to 2, and the total books drops to 9

so the probability the second time is 2/9

now multiply these two values to find the probability of both being science books

3/10 x 2/9

= 6/90

= 1/15