A researcher believes that 52.5% of people who grew up as the only child have an IQ score over 100. However, unknown to the researcher, this figure is actually 50%, which is the same as in the general population.To attempt to find evidence for the claim, the researcher is going to take a random sample of 400 people who grew up as the only child. Let p be the proportion of people in the sample with an IQ score above 100.
Answer the following:
a) Find the
b)Find the standard deviation of p:
c) Compute an approximation for P(p ≥ 0.525), which is the
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