Statistics Probability

Assume that in your History class you have earned test scores of 78, 82, 56, and 72.  Only 1 test remains.  If you need a mean score of 75 to earn a C in the class, what must you score on the final test?

• 75

• 87

• 12

• 57

Find the mean and standard deviation (Sx) for the following data set:

89, 72, 100, 87, 65, 98, 77, 92

• 85, 12.5

• 75.3, 30.65

• 85, 11.7

• 88, 12.5

What percent of data on normal curve is between z=0 and z=1.23?

• 68%

• 12%

• 89%

• 38.9%

What percent of data on a normal curve is above z=1.45?

• 92.5%

• 42.5%

• 7.4%

• 34%

What percent of data on a normal curve is below z= -1.4?

• 8%

• 92%

• 58%

• 5%

Find the z score if the mean is 80, standard deviation is 5, and x=87.

• -1.4

• 1.4

• -1.75

• 1.75

Find x if the mean is 20, standard deviation is 6, and z=1.32.

• 32.4

• 7.92

• -12.08

• 27.92

Assume the distribution of the heart rates of 21 year old females at rest is 68 bpm with a standard deviation of 4 bpm. If 200 women are tested, how many would have a heart rate less than 75 bpm?

• 96

• 192

• 8

• 4

Assume that the math SAT scores are normally distributed with a mean of 500 and a standard deviation of 100. If you score 480 on the math portion, what percent of those taking the test scored above you?

• 42%

• 58%

• 98%

• 92%

You draw a card from a standard deck. What is P(heart|red)?