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Question
If a = 6 and d = 10, then find S10.
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Solution
a = 6 and d = 10 ...[Given]
Since `S_n = n/2[2a + (n - 1)d]`,
`S_10 = 10/2 [2(6) + (10 - 1)(10)]`
= 5[12 + 9(10)]
= 5(12 + 90)
= 5(102)
= 510
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