Question

In: Statistics and Probability

5. X is a normally distributed random variable with a mean of 8 and a standard...

5. X is a normally distributed random variable with a mean of 8 and a standard deviation of 3. The probability that X is between 6 and 10 is

a. 0.7486

b. 0.4972

c. 0.6826

d. 0.8413

The weight of football players is normally distributed with a mean of 200 pounds and a standard deviation of 20 pounds.

6. The probability of a player weighing more than 240 pounds is

a. 0.0197

b. 0.9803

c. 0.4803

d. 0.0228

7. Refer to the information in Q6. The probability of a player weighing less than 220 pounds is

a. 0.8413

b. 0.9938

c. 0.4938

d. 0.1587

8. What percent of players weigh between 170 and 230 pounds?

a. 50%

b. 86.64%

c. 68.26%

d. 99.72%

A professor at a local university noted that the grades of her students were normally distributed with a mean of 76 and a standard deviation of 10.

9. The professor has informed us that 16.6 percent of her students received grades of A. What is the minimum score needed to receive a grade of A?

a. 85.7

b. 87.7

c. 88.3

d. 88.7

Expert Solution

orchestra answered 2 years ago

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