Last year,10 percent of all teenagers in Greenville purchased a new iPhone.This year,a sample of 260 randomly chosen Greenville teenagers showed that 39 had purchased a new iPhone.To test whether the percentage has risen,the p-value is approximately

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The p-value is the probability of getting a sample result as extreme as or more extreme than the one observed, assuming the null hypothesis is true. In this case, the null hypothesis is that the percentage of teenagers who purchased a new iPhone has not changed from last year, which is 10%. The sample result is that 39 out of 260 teenagers purchased a new iPhone, which is a proportion of 39/260 = 0.15. To calculate the p-value, we can use a binomial distribution with n = 260 and p = 0.10. The p-value is the probability of getting a proportion of 0.15 or more extreme, which is approximately 0.0036.

Last Year,10 Percent of All Teenagers in Greenville Purchased a New