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Question
If third term and fifth term of an A.P. are 13 and 25 respectively, find its 7th term.
Options
30
33
37
38
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Solution
37
Explanation:
t3 = 13
∴ a + 2d = 13 ...(i)
t5 = 25
∴ a + 4d = 25 ...(ii)
Solving (i) and (ii), we get
a = 1, d = 6
∴ t7 = a + 6d
= 1 + 6(6)
= 37
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