CBSE NCERT Solutions Chapter 5 Arithmetic Progressions Exercise 5.2 Question 2
2. Choose the correct choice in the following and justify:
(i) 30th term of the AP:
, is
(A) 97 (B) 77 (C) -77 (D) -87
(ii) 11th term of the AP:
, is
(A) 28 (B) 22 (C) -38 (D)
Solution (i)
First term = a =10
Common difference = d = 7- 10 = 4-7 = -3
n = 30 {Because, we need to find 30th term}
Therefore, the answer is (C)
Solution (ii)
First term = a = -3
Common difference = d =
n = 11 (Because, we need to find 11th term)
Using formula
, to find 11th term, we get
Therefore 11th term is 22 which means answer is (B).
deeraj says
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