Question

In the given A.P. 13, 8, 3, -2, --- value of the n(th) term is :

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Answer 1

Value of nth term is 13 + (n-1) × (8-13) = 18-5n

Answer 2

Answer:

The given AP is 3, 8,13,18....

Here, a = 3 and d = 8 – 3 = 5

∴ a30 – a20

=[3 + (30 – 1)5]- [3 + (20 – 1)5]

= 148 – 98 = 50

Thus, the required value is 50