The GMAC Insurance company reported that the mean score on the National Drivers Test was 82.5...

The GMAC Insurance company reported that the mean score on the National Drivers Test was 82.5 with a standard deviation of 3.3 points. The test scores are approximately bell-shaped. Approximately 68% of all test scores were between two values A and B. What is the value of A? Write only a number as your answer. Round to one decimal place.

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Expert Solution

Answer:

Given that:

The GMAC Insurance company reported that the mean score on the National Drivers Test was 82.5 with a standard deviation of 3.3 points.

= 82.5 , = 3.3

According to Emperical (68 - 95 - 99.7) rule,

Approximately 68% data falls in 1 standard deviation of the mean.

That is 68% data falls in the interval of

If 68% of all test scores were between A and B, the and

Put the values of and and find value for A

orchestra answered 2 years ago

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