Question

Scores on a standardized test are normally distributed with a mean of 228 and a standard deviation of 18. Students who score at least 2.3 standard deviations above the mean receive a certificate.

What is the minimum score required to receive the certificate?

Answer 1

270

Explanation:

The mean is 228 and the standard deviation is 18.

2.3 standard deviations above the mean is:

228 + 2.3×18

228 + 41.4

269.4

Since scores are usually integers, we round up to 270.