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प्रश्न
If a = 6 and d = 10, then find S10
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उत्तर
a = 6 and d = 10 ......[Given]
Since Sn = `"n"/2[2"a" + ("n" - 1)"d"]`,
S10 = `10/2 [2(6) + (10 - 1)(10)]`
= 5[12 + 9 (10)]
= 5(12 + 90)
= 5(102)
= 510
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