A man saved ₹ 33,000 in 10 months. In each month after the first, he saves ₹ 100 more than he did in the preceding month. How much did he save in the first month?

The general term of an A.P. whose first term is a and common difference is d, is given by:

1. T_n = 2a + (n − 1)d

2. T_n = $\dfrac{n}{2}[2a + (n − 1)d]$

3. T_n = a + (n − 1)d

4. T_n = $\dfrac{n}{2}[a + (n − 1)d]$

Sum of n terms of an A.P. whose first term is a and common difference is d, is given by:

1. S_n = $\dfrac{n}{2}[a + (n − 1)d]$

2. S_n = $\dfrac{n}{2}[2a + (n + 1)d]$

3. S_n = $\dfrac{n}{2}[2a − (n − 1)d]$

4. S_n = $\dfrac{n}{2}[2a + (n − 1)d]$

Sum of n terms of an A.P. whose first term and last term are a and l respectively is given by:

1. S_n = $\dfrac{n}{2}(a + l)$

2. S_n = $\dfrac{n}{2}(a − l)$

3. S_n = $\dfrac{n}{2}(2a + l)$

4. S_n = $\dfrac{n}{2}[a + (n − 1)l]$