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Question
Find the term t15 of an A.P. : 4, 9, 14, …………..
Solution
We need to find the 15th term of the A.P., 4, 9, 14
Here, the initial term is, a = 4.
Common difference = 14 - 9 = 9 - 4 = 5
The general term of an A.P is given by the formula,
tn = a + (n - 1)d
t15 = 4 + (15 - 1) × 5
t15 = 4 + 14 × 5
t15 = 4 + 70
t15 = 74
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