Kiran has $100 in her piggy bank. How much will she have in her bank 30 weeks from now if she puts $1 in the bank next week, $2 two weeks from now, $3 three weeks from now, and continues to increase the amount that she puts in by $1 each week?
Select:
A) 500  B) 525  C) 535  D) 565  E) 575
The dollar deposits are in an A.P.   1,2,3,4...30 with common difference 1   Sum of the terms is n(n+1) / 2   i.e 30 * (30+1) /2   = 30 * 31/2= 
<gadget id="calculator">30 * 31/2</gadget>
<output>465</output>
465   Total deposit therefore with Chiu-Lihas is 100 + 465= 
<gadget id="calculator">100 + 465</gadget>
<output>565</output>
565$
<result>D</result>
Kiran has $100 in her piggy bank. How much will she have in her bank 30 weeks from now if she puts $1 in the bank next week, $2 two weeks from now, $3 three weeks from now, and continues to increase the amount that she puts in by $1 each week?