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Question
If d = – 5, n = 10, an = 68, then find the first term.
Options
113
23
– 113
– 23
Solution
113
Explanation:
Given: d = – 5, n = 10, an = 68
Now, we know
an = a + (n – 1)d
68 = a + (10 – 1) (– 5)
68 = a + (9) ( – 5) = a – 45
a = 68 + 45
= 113
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