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Question
Find the 19th term of the A.P. 7, 13, 19, 25, ............ .
Solution
7, 13, 19, 25, ............ .
a = 7, n = 19, d = 13 – 7 = 6
an = a + (n – 1) d
a19 = 7 + (19 – 1) 6
= 7 + 18(6)
= 115
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