Suppose the mean percentage in Algebra 2B is 70% and the standard deviation is 8%. What percentage of students receive between a 62% and 94%?

Answer 1

Z-value is what we called the number of standard deviations from the mean. 62% is 8% one standard deviation to the left, or a Z-value of -1. 94 is 24% to the right of the mean, or 3 standard deviations for a z-value of three. You can look on a Z-table to find the area between -1 and 3, which is .840 or 84%