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December 22, 2014

December 22, 2014

Posted by **lindsay** on Tuesday, July 22, 2014 at 2:53pm.

- math -
**Reiny**, Tuesday, July 22, 2014 at 6:14pmsum(n) = (n/2)(first + last)

sum(11) = (11/2)(1+6)

= 77/2

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