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November 23, 2014

November 23, 2014

Posted by **jasmine** on Saturday, September 24, 2011 at 11:34pm.

- maths -
**Steve**, Monday, September 26, 2011 at 10:51amSay there are n scores. If the mean is 64, then the total points is just 64n.

Now, we have one more score, and the mean rises to 65. So, we have n+1 scores with mean 65. And we have added 80 points to the total.

64n+80 = 65(n+1)

64n+80 = 65n+65

n = 15

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