Question

Suppose that IQ scores have a bell-shaped distribution with a mean of 98 and a standard deviation of 17. Using the empirical rule, what percentage of IQ scores are greater than 115? Please do not round your answer.

Answer 1

Solution :

Given that,

= 98

= 17

Using Empirical rule,

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

P(98 - 1 * 17 < X < 98 + 1 * 17) = 68%

P(81 < X < 115) = 68%

Here ,

P(X > 115) = 1 - P(X < 115) = 1 - 84% = 16%

Answer = 16%