Question

Suppose that IQ scores have a bell-shaped distribution with a mean of 99 99 and a standard deviation of 13 13 . Using the empirical rule, what percentage of IQ scores are less than 86 86 ? Please do not round your answer.

Answer 1

Solution :

Given that,

= 99

= 13

Using Empirical rule,

P( - 1< X < + 1) = 68%

P( - 2< X < + 2) = 95%

P( - 3< X < + 3) = 99.7%

P(x < 86) = 0.16