1. The Vardon Exploration Company is getting ready to leave for South America to explore for oil. One piece of equipment requires 10 batteries that must operate for more than 2 hours. The batteries being used have a 15 percent chance of failing within 2 hours. The exploration leader plans to take 15 batteries. Assuming that the conditions of the binomial apply, the probability that the supply of batteries will contain enough good ones to operate the equipment is:

1-0.0449.

2- 0.9832.

3- 0.0132.

4- 0.9964.

Which one of the following is NOT statistical sampling?

Simple random sample.

Stratified random sampling.

Cluster sampling.

Convenience sampling.

1. Which of the following is an acceptable format for setting up class boundaries for a frequency distribution?
2. 20 to under 40.
3. 20 to 40.
4. 200 to 299.99.
5. All of the above.

1. Which of the following is a key difference between a bar chart and a histogram?
2. A bar chart typically has gaps between the bars while a histogram has no gaps.
3. A bar chart is developed to analyze a continuous variable, while a histogram is used to analyze discrete variables.
4. Both A and B are correct.
5. There is actually no real difference between a bar chart and a histogram.

QUESTION 8

1. The mayor of a large U.S. city is interested in addressing complaints from many property owners regarding recent property assessments. Many people feel that they are being overtaxed and that their assessments are too high. To study this issue, the mayor plans to hire consultants to randomly select homes in the city and have these homes independently assessed for value. However, she is concerned that the cost of sampling will be very high since the city is spread out over a wide geographical area. To potentially reduce the cost of sampling, which of the following statistical sampling techniques should be applied?
2. Cluster sampling.
3. Ratio sampling.
4. Simple random sampling.
5. Stratified random sampling.

A report on spending by adults on recreation stated the following: At least 75 percent of the people in the survey spend between $750 and $1,250 per year. The report also said that at least 88 percent spend between $625 and $1,375 per year. Given this information, which of the following is most apt to be true?

The standard deviation is approximately $125.

The distribution of spending on recreation can be assumed to be bell-shaped.

The standard deviation is approximately $187.5.

The standard deviation is approximately $250.

1. Incomes in a particular market area are known to be right skewed with a mean equal to $33,100. In a report issued recently, a manager stated that at least 89 percent of all incomes are in the range of $26,700 to $39,500, and this was based on Tchebysheff's theorem. Given these facts, what is the standard deviation for the incomes in this market area?
2. Approximately $6,400.
3. Approximately $3,200.
4. Approximately $2,133.
5. Approximately $4,266.