On a standardized test, Phyllis scored 84, exactly one standard deviation about the mean. If the standard deviation for the test is 6, what is the mean score for the test?
78
To find the mean score for the test, we need to calculate it using the given information.
Since Phyllis scored 84, which is exactly one standard deviation above the mean, we can subtract 84 by one standard deviation: 84 - 6 = 78.
Therefore, the mean score for the test is 78.
To find the mean score for the test, we need to first understand what a standard deviation is. The standard deviation is a measure of how spread out the data is from the mean.
In this case, Phyllis scored 84, which is one standard deviation above the mean. Given that the standard deviation is 6, we can calculate the mean score using the following formula:
Mean = Score - (Standard Deviation * Number of Standard Deviations)
Let's substitute the values we have:
Mean = 84 - (6 * 1)
= 84 - 6
= 78
Therefore, the mean score for the test is 78.
I assume you mean above the mean.
Z = (score-mean)/SD
Z = +1
Insert values and calculate.