Suppose you just recieved a shipment of 15 televisions. 4 of the 15 are defective. If 2 of them are randomly selected, what is the probability they both work?

Question

Please also answer the probability of 1 of the 2 randomly selected is defective

Answer 1

For the first pick:

 

11/15

 

For the second pick

 

10/14

 

For both both picks

 

110 / 210

11/21