A Factory Making Two Types of Computer Chip Mixes Up

Multiple Choice

A factory making two types of computer chip mixes up two small batches of new chips. A box contains 50 chips, 30 are type A and 20 type B. If you take two chips out at random, what are the chances they are both type B (3 decimal places) ?

A) 0.135
B) 0.145
C) 0.155
D) 0.165