A blind taste test is done to compare Cola 1 and Cola 2. Among n = 75 participants, =.64 is the proportion preferring Cola 1. If, actually, the two colas are equally preferred in a larger population...

A blind taste test is done to compare Cola 1 and Cola 2. Among n = 75 participants,

=.64 is the proportion preferring Cola 1. If, actually, the two colas are equally preferred in a larger population of tasters, p = .5 is the corresponding population proportion. Assuming that p = .5, find the value of the standardized statistic (z-score) for the sample proportion observed in the taste test.