Question:
If 19th term of a non-zero A.P. is zero, then its (49th term) : (29th term) is :
If 19th term of a non-zero A.P. is zero, then its (49th term) : (29th term) is :
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Use a + 18d = 0 to write every term as a multiple of d.
Updated On: Nov 5, 2026
- 2 : 1
- 4 : 1
- 1 : 3
- 3 : 1
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The Correct Option is D
Solution and Explanation
Let the first term be a and the common difference d. The 19th term is \(a + 18d = 0\), so \(a = -18d\) (d is non-zero, otherwise all terms would be zero).
49th term = \(a + 48d = 30d\). 29th term = \(a + 28d = 10d\).
Ratio = \(30d : 10d = 3 : 1\).
Answer: (4) 3 : 1
49th term = \(a + 48d = 30d\). 29th term = \(a + 28d = 10d\).
Ratio = \(30d : 10d = 3 : 1\).
Answer: (4) 3 : 1
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