In what time will Rs.1000 become Rs.1331 at 10% per annum compounded annually?

Principal = Rs.1000;

Amount = Rs.1331;

Rate = Rs.10%p.a.

Let the time be n years.Then

[1000(1+10/100)Λn;]

= 1331.

= (1331/1000)

= (11/10)³

Therefore n = 3 years.