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On a test that has a normal distribution, a score of 41 falls three standard deviations below the mean, and a score of 73 falls one standard deviation above the mean. Determine the mean of this test.

User Everon
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2 Answers

3 votes

Answer:

its actually 35

Explanation:

User Jeff
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4 votes

Answer:

The mean of the test is 65

Explanation:

Let the mean be x and SD be y

3 SD BELOW the mean means that we are taking away 3 SD FROM the mean

Mathematically, we have that as;

x - 3y = 41 •••••(i)

73 is 1 SD above mean

Mathematically;

x + y = 73 ••••••••(ii)

So let us solve both equations simultaneously

Simply multiply equation ii by 3 then add to i

x - 3y = 41

3x + 3y =219

4x = 41 + 219

4x = 260

x = 260/4

x = 65

User Ralph Tandetzky
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