In a box of 10 pencils, a total of 2 are defective. If a customer buys 3 pencils selected at random from the box, what is the probability that neither pencils will be defective? Choose the most appropriate option:
A) 1/12
B) 7/15
C) 2/13
D) 2/15
E) 1/17
First, there are 8C3 ways you can select 3 good pencils from 4 good ones.   Second, there are 10C3 ways you select 3 pencils from 6 ones in the box.   Then, the probability that neither pen will be defective is: 8C3/10C3=56/120 =7/15   Answer is 7/15
<result>B</result>
In a box of 10 pencils, a total of 2 are defective. If a customer buys 3 pencils selected at random from the box, what is the probability that neither pencils will be defective?