Question

Priya earned ₹ 15,000 in the first month. Thereafter her salary increased by ₹ 1500 per year. Her expenses are ₹ 13,000 during the first year and the expenses increase by ₹ 900 per year. How long will it take for her to save ₹ 20,000 per month

Answer 1

	Yearly Salary	Yearly expenses	Yearly saving
1st year	15000	13000	2000
2nd year	16500	13900	2600
3rd year	18000	14800	3200

We find that the yearly savings are in A.P. with a₁ = 2000 and d = 600.

We are required to find how many years are required to save 20,000 a year …………..

a_n = 20,000

a_n = a + (n – 1)d

20000 = 2000 + (n – 1)600

(n – 1)600 = 18000

n – 1 =  `18000/600` = 30

n = 31 years