Question:medium
The first term of an A.P. is $148$ and the common difference is $-2$. If the A.M. of first $n$ terms of the A.P. is $125$, then the value of $n$ is
The first term of an A.P. is $148$ and the common difference is $-2$. If the A.M. of first $n$ terms of the A.P. is $125$, then the value of $n$ is
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Mean of A.P. simplifies nicely to $\frac{1}{2}[2a+(n-1)d]$, no need to compute full sum.
Updated On: May 8, 2026
- $18$
- $24$
- $30$
- $36$
- $48$
Show Solution
The Correct Option is B
Solution and Explanation
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