Question

Amit saves a certain amount every month in a specific way. In the first month, he saves Rs. 200, in the second month Rs. 250, in the third month Rs.300 and so on. How much will be his total savings in 17 months?

Answer 1

a = 200

d = 250 – 200 = 50

n = 17

t_n = ?

S_n = `n/2[2a + (n - 1)d]`

`S_17 = 17/2 [2(200) + (17 - 1)50]` 

`= 17/2[400 + 800]`

`= 17/2[1200]`

= 17 × 600

= 10200

∴ Amit will save Rs. 10200 in 17 months.