Question

Ravi saves certain amount every month in a specific way. In the first month he saves ₹50, in the second month ₹100, in the third month ₹150 and so on. How much will be his total savings in 10 months?​

Answer 1

$\huge\boxed{\fcolorbox{black}{pink}{Solution}}$

$\sf{a= 50}$

$\sf{d = 100-50} = 50$

$\sf{n = 10}$

$\sf{tn = ?}$

$\sf{Sn = \frac{n}{2} [2a+(n-1)d]}$

$\sf{S10 = \frac{10}{2} [2(50)+(10-1)50]}$

$\implies\sf{ \frac{10}{2} [100+450]}$

$\implies\sf{ \frac{10}{2} [550]}$

$\implies\sf{2,750}$

$\sf{ ∴ Ravi \: will \: save \: Rs. \: 2,750 \: in \: 10 \: months. }$