The senior class GPA is 86, with a standard deviation of 6. Chaska has a GPA of 98. What percentage of seniors have a GPA higher than Chaska’s?
98 is tow standard deviations above the mean ( 86 + 2 *6 = 98)
Look at the Bell curve below....
approx 2.1% are above that
For a more exact answer, look at your z-score tables to find z for 98 (2 s.d. above mean) = .9772
so scores ABOVE would be 1 - .9772 = .0228 or 2.28% are above 98
