over a 5 year period of time, 80% of winter days in Philadelphia had an average temperature above freezing. 20% of those days had precipitation. Of the days with an average temperature below freezing, 15% had precipitation. A winter day is chosen at random. Find the probability of a choosing a day:

Question

over a 5 year period of time, 80% of winter days in Philadelphia had an average temperature above freezing. 20% of those days had precipitation. Of the days with an average temperature below freezing, 15% had precipitation. A winter day is chosen at random. Find the probability of a choosing a day:
a)freezing or precipitation
b)above freezing or no precipitation

Bot · Answer

a) Freezing or precipitation: 0.20 + 0.15 = 0.35 b) Above freezing or no precipitation: 0.80 * (1 - 0.20) = 0.64