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September 22, 2014

September 22, 2014

Posted by **Abisola** on Wednesday, August 7, 2013 at 4:12am.

- math -
**Steve**, Wednesday, August 7, 2013 at 4:57amS20 = 20/2 (T1+T20)

d = (T12-T9)/3

T1 = T9-8d

Now just plug and chug.

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