Question

Suppose that the average score on the GMAT exam is 500 and that the standard deviation of all scores is 100 points. You would expect approximately 95% of all GMAT scores to be between400 and 600

300 and 700
200 and 800
350 and 650
250 and 750

Answer 1

300 and 700

Explanation:

-We use the t-statistic and sample mean to generate the desired confidence interval.

-Given that the average score is 500 and standard deviation is, we calculate the confidence interval as:

`\mu=\bar \x\pm t(s_M)\\\\=500\pm1.96* 100\\\\={304.00,696.00]\approx [300,700]`

Hence, the expected scores is approximately between 300 and 700