If the sum of `m` terms of an A.P., is `3m^2+5m` then which of its terms is 164?
a.`26 t h` b. `27 t h` c. `28 t h` d. none of these

Explanation

To solve the problem step by step, we need to determine which term of the arithmetic progression (A.P.) is equal to 164, given that the sum of the first `m` terms is `3m^2 + 5m`.

### Step 1: Understand the formula for the nth term
The nth term of an A.P. can be calculated using the formula:
\[ a_n = S_n - S_{n-1} \]
where \( S_n \) is the sum of the first `n` terms, and \( S_{n-1} \) is the sum of the first `n-1` terms.

### Step 2: Write down the expression for \( S_n \)
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