Question

MCQs
Mark the correct alternative in each of the following:
1. If 7th and 13th terms of an A.P. be 34 and 64 respectively, then its 18th term is
(a) 87
(b) 88
(C) 89
(d) 90​

Answer 1

Answer:

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Answer 2

Answer:

. (c) 89

Step-by-step explanation:

a + 12d = 64.....i

a + 6d = 34 ....... ii

subtracting eq. ii from eq. i , we have

6d = 30 or d = 5

so , a = 4

so 18 th term is a + 17d = 4 + (17 ×5) = 89

hence answer is (c) 89