Mathematics
If a = 3, n = 8 and Sn = 192, then the common difference of the A.P. is:
4
5
6
7
AP
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Answer
a = 3
n = 8
Sn = 192
Sn = [2a + (n - 1)d]
⇒ 192 = [2(3) + (8 - 1)d]
⇒ 192 = 4[6 + 7d]
⇒ = [6 + 7d]
⇒ 48 = [6 + 7d]
⇒ 48 - 6 = 7d
⇒ 42 = 7d
⇒ d =
⇒ d = 6.
Hence, option 3 is the correct option.
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