Teacher Licensing Examination Questions
Praxis: The hand spans of ninth-grade students at Martin Luther King, Jr. High are approximately normally distributed, with a mean of 7 inches and a standard deviation of 1 inch. Of the following groups of measurements of hand span, which is expected to contain the largest number of ninth-graders?
A)less than 6 inches
B)greater than 7 inches
C)between 6 and 8 inches
D)between 5 and 7 inches

Question

Quizplus · Accepted Answer

The mean of 7 inches indicates the center of the distribution, and since the standard deviation is 1 inch, we can infer that approximately 68% of students have hand spans between 6 and 8 inches (one standard deviation above and below the mean). Therefore, choice C, "between 6 and 8 inches," is expected to contain the largest number of ninth-graders.