The 3rd and 8th term of an arithmetic progression is -13 and 2 respectively. What is the 14th term?
The 3rd and 8th term of an arithmetic progression is -13 and 2 respectively. What is the 14th term? Correct Answer 20
If a is the first term and d is the common difference then the third term of the AP is given by
a + 2d = -13 ----(1)
And 8th term is given by
a + 7d = 2 ----(2)
Subject (1) from (2)
5d = 15
⇒ d = 3
Put in equation (1)
a = -13 - 6 = -19
14th term will be given as
a + 13d = -19 + 13 × 3 = -19 + 39 = 20
∴ The 14th term = 20
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Feb 20, 2025