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Question
1, 7, 13, 19 ...... find 18th term of this A.P.
Solution
The given A.P. is 1, 7, 13, 19, ......
Here, a = 1, d = 7 – 1 = 6
Since tn = a + (n – 1)d,
t18 = 1 + (18 – 1)(6)
= 1 + 17(6)
= 1 + 102
= 103
∴ 18th term of the given A.P. is 103.
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