A man saved ₹660000 in 20 years. In each succeeding year after the first year, he saved ₹2000 more than what he saved in the previous year. How much did he save in the first year?
Given: -
Amount saved by a man in 20 years is Rs.660000
Let the amount saved by him in the first year be $a$.
In every succeeding year, he saves Rs.2000 more than what he saved in the previous year.
Increment of saving of the year when compared last year is Rs. 2000
Hint: - The above information looks like the savings are in Arithmetic Progression.
Amount saved in first year $=\mathrm{a}$
Common difference $=\mathrm{d}=₹ 2000$
Total number of years $=\mathrm{n}=20$
The total amount saved in 20 years is $₹ 660000$
Sum of $n$ terms in an A.P $=\frac{n}{2}[2 \times a+(n-1) \times d]$
$660000=\frac{20}{2}[2 \times a+(20-1) \times 2000]$
a = 14000
∴ In the first year, he saved ₹14000.