Question

5. There are 400 students in the senior class at Oak Creek High School. All 2 points

of these students took the SAT. The distribution of their SAT scores is
approximately normal. The number of students who scored within 2
standard deviations of the mean is approximately *
-3
-2
0
1
2.
3

Answer 1

Answer: 380

Step-by-step explanation: 95% of 400 is 380

Answer 2

The number of students who scored within 2 standard deviations of the mean is 380.

Explanation:

The Empirical Rule states that, for a normally distributed random variable:

68% of the measures are within 1 standard deviation of the mean.

95% of the measures are within 2 standard deviation of the mean.

99.7% of the measures are within 3 standard deviations of the mean.

The number of students who scored within 2 standard deviations of the mean is approximately

By the Empirical Rule, 95% of the students scored within 2 standard deviations of the mean

Out of 400

0.95*400 = 380

The number of students who scored within 2 standard deviations of the mean is 380.