List of top Mathematics Questions on nth Term of an AP asked in BITSAT

The sum of the first \(20\) terms of an arithmetic progression is \(640\), and the difference between the \(15^\text{th}\) and \(5^\text{th}\) terms is \(30\). Find the first term of the A.P.

If $\log a, \log b$, and $\log c$ are in A.P. and also $\log a-\log 2 b, \log 2 b-\log 3 c, \log 3 c-\log a$ are in A.P., then

If $m$ arithmetic means are inserted between $1$ and $31$ so that the ratio of the $7^{th}$ and $(m - 1)^{th}$ means is $5 : 9$, then find the value of m.