Question

Find the indicated IQ score. The graph to the right depicts IQ scores of​ adults, and those scores are normally distributed with a mean of 100 and a standard deviation of 15. Click to view page 1 of the table. LOADING... Click to view page 2 of the table. LOADING... x0.65 A graph with a bell-shaped curve, divided into 2 regions by a line from top to bottom, on the right side. The region left of the line is shaded and labeled 0.65. The x-axis below the line is labeled "x". The indicated IQ​ score, x, is nothing. ​(Round to one decimal place as​ needed.)

Answer 1

Let's write the given information:

Let X be a random variable which takes the values of IQ scores.

From the given information X follows normal distribution with mean( ) = 100 and standard deviation ( ) = 15

Here, we have given that the area left to the x is 0.65

So we need to find z score for probability 0.65

z_c = "=NORMSINV(0.65)" = 0.3853

Formula of x score is as follows:

x = + (z_{c *} ) = 100 + (0.3853*15) = 105.7798 = 105.8 (after rounding)