Consider a normal distribution curve where 70-th percentile is at 12 and the 45-th percentile is at 7. Use this information to find the mean, μ, and the standard deviation, o, of the distribution. a) μ = b) σ =

The IQ's in a certain population are normally distributed with a mean score of 104 and a standard deviation of 14. If we select a person at random from this population, find the probability that their IQ will be: 1. Find the 67th percentile of IQ's in this population. 2. Find the 20 The percentile of IQ's in this population 3. Find the IQR of IQ's in this population.

Sketch a standard normal curve and shade the area that lies to the left of a. 2.15, b. - 1.61, c. 0, and d. - 7. Then determine the area under the standard normal curve that lies in the area of interest for each part. Click here to view page 1 of the normal distribution table. Click here to view page 2 of the normal distribution table. c. Sketch a standard normal curve and shade the area under the curve that lies to the left of 0. Choose the correct graph below. A. 0 Z G OB. 0 The area to the left of 0 is (Round to four decimal places as needed.) O C. -1 0 O D. -1 0 Time Remaining: 01:09:16 Next

Assume that the distribution of scores on a college entrance exam is normally distributed with a mean of 490 and a standard deviation of 43. For each score in the table below, convert the raw score into a corresponding z-score. original score Z-score 621 398 586 710