Stating Conclusions About Claims. In Exercises 1–4, make a decision about the given claim. Use only the rare event rule stated in Section 8-2, and make subjective estimates to determine whether events...

Stating Conclusions About Claims. In Exercises 1–4, make a decision about the given claim. Use only the rare event rule stated in Section 8-2, and make subjective estimates to determine whether events are likely. For example, if the claim is that a coin favors heads and sample results consist of 11 heads in 20 flips, conclude that there is not sufficient evidence to support the claim that the coin favors heads (because it is easy to get 11 heads in 20 flips by chance with a fair coin).

1.
Claim: A coin favors heads when tossed, and there are 90 heads in 100 tosses.

2.
Claim: The proportion of households with telephones is greater than the proportion of 0.35 found in the year 1920. A recent simple random sample of 2480 households results in a proportion of 0.955 households with telephones (based on data from the U.S. Census Bureau).

3.
Claim: The mean pulse rate (in beats per minute) of students of the author is less than 75. A simple random sample of students has a mean pulse rate of 74.4.

4.
Claim: Movie patrons have IQ scores with a standard deviation that is less than the standard deviation of 15 for the general population. A simple random sample of 40 movie patrons results in IQ scores with a standard deviation of 14.8.