Suppose You Have a Random Sample of 200 Students' GMAT $\left( \frac { 50 } { \sqrt { 200 } } \right)$

Multiple Choice

Suppose you have a random sample of 200 students' GMAT scores that have a sample mean of 700 and sample standard deviation of 50, and would like to calculate the 90 percent confidence interval of the population mean. Which of the following would be the correct construction?

A) 700 ± 1.65 $\left( \frac { 50 } { \sqrt { 200 } } \right)$
B) 700 ± 1.96 $\left( \frac { 50 } { \sqrt { 200 } } \right)$
C) 700 ± 1.65 $\left( \frac { 50 } { 200 } \right)$
D) 700 ± 1.96 $\left( \frac { 50 } { 200 } \right)$