Iq scores are normally distributed with a mean of 100 and a standard deviation of 15. a. calculate the probability of finding a genius (iq > 130). b. calculate the probability of average intelligence (between 90 and 110).

Mean is and a standard deviation is , then the variable .

Use substitution

.

This substitution gives you that .

a. For X=130, and (the decimal value is taken from the Standard Normal Distribution Table).

b. For X=90, and for X=110, . Then (the decimal value is taken from the Standard Normal Distribution Table).

the final function for the graph becomes x-2=-1. before graphing you solve the equation, where x=1. then graph accordingly.   ( on the x-axis, 1 on the line will possess a vertical line.)

horizontal translation of 2 units in the positive x direction

followed by

vertical translation of 3 units in the positive y direction