Question 1121138
Note:  I edited the rain probability as 0.15, so the probability of one or the other added to 1.00

R=0.15-----R 0.15--0.0225(both days)
-----------NR0.85--0.1275 (1 day)
NR=0.85---R 0.12--0.1275 (1 day)
-----------NR 0.85--0.7225 (0 days)

The probability of at least one rainy day is 0.2775.

This is the same as 1- probability of no rain either day (0.7225).