A survey shows that 75% of the households in a large town have microwave ovens. If 20 houses are selected at random, find the following: just set up. Do NOT evaluate. A) the probability that no more than one of these households has a microwave oven. B) the probability that at least 3 of these households have a microwave oven. For part a, is it probability of both x=0 and x=1 subtracted from one? I always get confused when I see the phrase "no more than". And for part b is it just exactly p(x=3) since it has the words at least?

Question

A survey shows that 75% of the households in a large town have microwave ovens. If 20 houses are selected at random, find the following: just set up. Do NOT evaluate.                                                 A) the probability that no more than one of these households has a microwave oven.                              B) the probability that at least 3 of these households have a microwave oven.                                    For part a, is it probability of both x=0 and x=1 subtracted from one? I always get confused when I see the phrase "no more than". And for part b is it just exactly p(x=3) since it has the words at least?