a score that is 8 points above the mean corresponds to a
z-score = 0.50. What is the population standard deviation?
2006-10-04 15:48:42 · 2 answers · asked by .......... 4 in Science & Mathematics ➔ Mathematics
z score = (raw score - mean)/standard deviation. so if (raw score - mean) = 8 and the z-score is .5, then the equation would be 8/x=.5 so the standard deviation = 16.
2006-10-04 16:00:35 · answer #1 · answered by Anonymous · 0⤊ 0⤋
All you need to know to solve this problem is the definition of z-score, so here it is:
z-score is equal to the observed score, less the mean score, divided by the standard deviation.
In this problem, you are told that the observed score less the mean score is 8 points. So the z-score is 8 points divided by the standard deviation.
You know that the z-score is 0.50. If we represent the standard deviation by x, then we know that 8 / x = 0.50
With that information, you should be able to calculate the standard deviation (x).
Good luck!
2006-10-04 23:01:32 · answer #2 · answered by actuator 5 · 0⤊ 0⤋