Question

1. If the heights of ice hockey goalies are normally distributed with the mean μ=72μ=72 inches and the standard deviation σ=5.4σ=5.4 inches. What is the percentage of hockey players that have the height between 66.666.6 and 77.477.4 inches?

a. 68%

b. 50%

c. 32%

d. 95%

2. Diagnostic tests of medical conditions can have several types of results. The test result can be positive or negative, whether or not a patient has the condition. A positive test (+) indicates that the patient has the condition. A negative test (−) indicates that the patient does not have the condition. Remember, a positive test does not prove the patient has the condition. Additional medical work may be required. Consider a random sample of 200 patients, some of whom have a medical condition and some of whom do not. Results of a new diagnostic test for a condition are shown.

Calculate P(−|ConditionPresent)P(−|ConditionPresent)

Select one:

a. 101/200

b. 101/119

c. 18/119

d. 18/200

Answer 1

Ans:

1)

66.6 and 77.4 are one standard deviation below and above the mean respectively.

68% of the data falls within one standard deviation of mean.

Option a is correct.

68%

2)

P(−|ConditionPresent) is a conditional probbaility,so option a and d are not correct.

Number of subjects having a medical condition=119

Out of 119 subjects having medical condition,number of subject which gives negative test is 18

So,P(−|ConditionPresent)=18/119

Option c is correct.(18/119)