Use Problem 15 of this section to show that in n independent trials with probability p of success,
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Problem 15
Draw a graph of the equation y = x(1 - x) for x between 0 and 1. What is the maximum value of y? Why does this show that the variance (see Problem 10 in this section) of the "number of successes" random variable for n independent trials is less than or equal to n/4?