Scores on a college entrance examination are normally distributed with a mean of 500 and a standard deviation of 100. What percent of people who write this exam obtain scores between 425 and 575?
a. 27.34%
b. 45.32%
c. 54.68%
d. 77.34%
+37158 Are y'all working with z-scores? I'll have to look up my z-score table and get back in a few mins.....
well never mind the z-scores as this is a multiple choice....
ONE standard deviation above 500 and below 500 would be 400 and 600
from a standard bell curve, this represents 68%
question asks for 425 and 575 which would be slightly LESS than 68%
so answer C 54.68%
I will check z-scores to be sure....
OK....checked z-score tables and find 54.68%
