A candidate for mayor wants to gauge potential voter reaction to an increase recreational services b

A candidate for mayor wants to gauge potential voter reaction to an increase recreational services by estimating the proportion of voter who now use city services. If we assume that 50% of the voters require city recreational services, what is the probability that 40% or fewer voters in a sample of 100 actually will use these city services?

First, let's do a test on the proportion using our proportion hypothesis calculator:
We get Z = -2

Now use the z-score calculator to get P(z<-2) = 0.02275