Iq scores are known to be normally distributed. the mean iq score is 100 and the standard deviation is 15. the top 25% of the population (ranked by iq score) have iq’s above what value?

110

Step-by-step explanation:

We have been given that the mean IQ score is 100 and the standard deviation is 15.

We will use normal distribution table to solve our given problem.

The top 25% of the population will represent scores greater than 75%.      

The z-score corresponding to data greater than 75% is 0.6745.

Upon substituting our given values in z-score formula, we will get:

Therefore, the top 25% of the population (ranked by IQ score) have IQ’s above 110.

answer: 21$

step-by-step explanation:

$42 / $14 = 3   (ratio 3: 1)

$7 x 3 = $21

50.6

step-by-step explanation: