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 Rs. 20. After a year, how much money will she save? Will she be able to fulfil her dream of sending her daughter to school?

Explanation

As given Ramkali's savings are `50+70+90+...........` which is an AP


So,
`a_1=50,d=20,n=12`


Sum of series of an A.P. will be-


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