Question

19.

A math professor notices that scores from a recent exam are normally distributed with a mean of 73 and a standard deviation of 6.

(a) What score do 75% of the students exam scores fall below?
Answer:

(b) Suppose the professor decides to grade on a curve. If the professor wants 2.5% of the students to get an A, what is the minimum score for an A?
Answer:

20.

Scores on a certain intelligence test for children between ages 13 and 15 years are approximately normally distributed with μ=101μ=101 and σ=18σ=18.

(a) What proportion of children aged 13 to 15 years old have scores on this test above 91 ? (NOTE: Please enter your answer in decimal form. For example, 45.23% should be entered as 0.4523.)
Answer:

(b) Enter the score which marks the lowest 20 percent of the distribution.
Answer:

(c) Enter the score which marks the highest 5 percent of the distribution.
Answer:

Answer 1