A sample of 100 customers of Montana Gas and Electric resulted in the following frequency distribution of monthly charges.
Amount ($) Number
0-49 ...........................13
50-99 .........................22
100-149 ......................34
150-199 ......................26
200-249 ...................... 5
a. Let A be the event that monthly charges are $150 or more. Find P(A).
b. Let B be the event that monthly charges are less than $150. Find P(B).