Question

Practice Set 3.4
1. On 1" Jan 2016. Sanika decides to save 10, 11 on second day, 12 on third
day. If she decides to save like this, then on 31 Dec 2016 what would be her total savings? ​

Answer 1

Answer:

The savings of sanika is an A.P.

i.e.10,11,12,.......

2016 was a leap year.

Total days in that =366

i.e.n=366,a=10

d=t2-t1=11-10=1

Sn=n/2×{2a+(n-1)d}

S366 =366/2{2×10(366-1)×}

S366=183×20+365

S366=183×385

S366=70455

Hence,On 31st December 2016 the total savings of sanika will Rs70,455