About 30 % of Americans aged 19–28 claim that they have used an illicit drug other than marijuana. If a random sample of 40 Americans aged 19–28 finds 21 who claim to have used an illicit drug other...

About 30 % of Americans aged 19–28 claim that they have used an illicit drug other than marijuana. If a random sample of 40 Americans aged 19–28 finds 21 who claim to have used an illicit drug other than marijuana, would you be surprised? Explain these statistics.

Sherlock Holmes often used inference. He often discussed his process of “reasoning backwards”. Choose one of his cases and explain how inference was successfully employed.