Probability of no rain on June 1 = 1 - 1/2 = 1/2.
Probability of no rain on July 1 = 1 - 1/5 = 4/5.
Probability of no rain on August 1 = 1 - 2/3 = 1/3.
The probability that the city will receive rain on none of these days is:

The required value of probability is 2/15.