Question

Ramkali would need Rs.1800 for admission fee and books etc., for her daughter to start going to school from next year. She saved Rs.50 in the first month of this year and increased her monthly saving by 20. After a year, how much money will she save? Will she be able to fulfill her dream of sending her daughter to school?

Answer 1

Saving in a year =Rs 50+Rs 70+Rs 90+...Here, a=50, d=20 and n=12
Sn $=\frac{n}{2}[2a+(n-1\left)d\right]=\frac{12}{2}[2\times 50+(12-1\left)20\right]=6\times (100+220)=6\times 320=Rs1920$

Required amount for admission = Rs 1800
∴Saving=Rs 1920−Rs 1800=Rs 120