Kanika was given her pocket money on 1st January 2016.She puts Rs.1 on Day1, Rs 2 on Day2 Rs3 on Day3 and continued on doing so till the end of the month, from this money into her piggy bank . She also spent Rs.204 of her pocket money , and was found that at the end of the month she still has Rs.100 with her.How much money was her pocket money for the month.PLEASE DO IT .IT'S URGENT! !!!!
Answers & Comments
First term = 1 , Difference = 1
Sum = n / 2 [ 2a + (n - 1)d]
Sum = 31 / 2 [ 2 * 1 + (31 - 1)(1) ]
Sum = 31 / 2 [ 2 + 30 ]
Sum = (31 / 2) * 32
Sum = 31 * 16
Sum = 496
Now this Rs 496 has been put into piggy bank from the pocket money
Let the pocket money be x , also she spent Rs 204 ,Amount Remaining = 100
So , x - 496 - 204 = 100
x - 700 = 100
x = 800
Ans: Rs 800
@skb