A test was given to 120 students, and the scores aprrox. a normal distribution. If the mean score was 72 with a standard deviation of 7, approx. what percent of the scores were 65 or higher?
answer choices-
50%
68%
76%
84%
and please explain how you got it thanks so much!!
answer choices-
50%
68%
76%
84%
and please explain how you got it thanks so much!!
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68%
Explanation:
(to find out if it's 50%) 72+72=144
And that's not how many students took it it.
It can't be 76% because 76% of 120 is like 80. But in this case it is In the middle of 50 & 76 therefore it is 68%
Explanation:
(to find out if it's 50%) 72+72=144
And that's not how many students took it it.
It can't be 76% because 76% of 120 is like 80. But in this case it is In the middle of 50 & 76 therefore it is 68%
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You are wrong. The answer is 84%
http://upload.wikimedia.org/wikipedia/commons/8/8c/Standard_deviation_diagram.svg
The mean is 72 and the standard deviation is 7. This means that 65 is one standard deviation below normal. So you add 34.1+34.1+13.6+2.1+.1 to get 84
http://upload.wikimedia.org/wikipedia/commons/8/8c/Standard_deviation_diagram.svg
The mean is 72 and the standard deviation is 7. This means that 65 is one standard deviation below normal. So you add 34.1+34.1+13.6+2.1+.1 to get 84
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not sure sorry