Jawabanmu

2014-03-04T13:31:52+07:00
309 = 1 + (n-1).2 ---> n = 155
S =  \frac{155}{2} (1 + 309) = 155 x 200 = .... cari sendiri ya..
2014-03-04T14:13:43+07:00
309 = 1 + (n-1).2 ---> n = 155
S = (1 + 309) = 155 x 200 = .................................
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