Question

Find the indicated Probability.

1. A bank’s loan office uses credit scores in their application process. The credit scores are normally distributed with a mean of 705 and a standard deviation of 55. Applicants are offered loans if their credit scores are above 670. Find the probability that a randomly selected applicant will be offered a loan.

1. 1. 0.2611                          b.   0.3811                    c.   0.7389                     d.  0.0703
2. Scores on a test are normally distributed with a mean of 72.5 and a standard deviation of 9.1. Find , the test score which separates the bottom 80% from the top 20%. Round to the nearest tenth.

1. 51.3                             b.   64.9                         c.   80.1                        d. 93.7

3. In one region, the September energy consumption levels for single-family homes are found to be normally distributed with a mean of 990 kWh and a standard deviation of 198 kWh. For a randomly selected home, find the probability that the September energy consumption level is between 1100 kWh and 1250 kWh.

1. 0.1926                          b.   0.3828                    c.   0.6178                     d. 0.8074

4. The lengths of human pregnancies are normally distributed with a mean of 268 days and a standard deviation of 15 days. What is the probability that a pregnancy lasts less than 270 days?

1. 0.4813                          b.   0.5517                    c.   0.50            d.  0.4483

Answer 1