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Question
Find S10 if a = 6 and d = 3.
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Solution
a = 6 and d = 3 ...[Given]
Since `S_n = n/2[2a + (n - 1)d]`,
`S_10 = 10/2[2(6) + (10 - 1)(3)]`
= 5[12 + 9(3)]
= 5(12 + 27)
= 5(39)
= 195
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