Q: The mean and sd of the 8 nunbers are (shown below) are 10th and 0.3, respectively. What percent of the 8 numbers are within 1 sd of the mean?
9.4, 9.9, 9.9, 9.9, 10, 10.2, 10.2, 10.5
I failed to get the right answer.
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SD!
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shankar.ashwin
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Given S.D=0.3 and Mean =10
Within 1 SD means 10+ 0.3 (or) 9.7-10.3
Of the 8 numbers, 6 of them lie within this range (9.7-10.3)
6/8 * 100 = 75%
Within 1 SD means 10+ 0.3 (or) 9.7-10.3
Of the 8 numbers, 6 of them lie within this range (9.7-10.3)
6/8 * 100 = 75%
Last edited by shankar.ashwin on Mon Oct 31, 2011 10:19 pm, edited 1 time in total.
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Ahmed MS
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shankar.ashwin wrote:Given S.D=0.3 and Mean =10
Within 1 SD means 10+ 0.3 (or) 9.7-10.3
Of the 8 numbers, 6 of them lie within this range (9.7-10.3)
6/8 * 100 = 75%
Thanks for your easy and quick solution.
