Posted by **Tracy** on Saturday, March 29, 2014 at 10:07am.

Assume that event A occurs with probability 0.4 and event B occurs with probability 0.5. Assume that A and B are disjoint events.

The probability that either event occurs (A or B) is

A. 0.0

B. 0.7

C. 0.9

D. 1.0.