Question

find the compound interest when principal is rupees 2,000 and the rate is 10% per annum compounded annually for 2 years

Answer 1

CI=2000((1+10/100)*(1+10/100))-1
=2000*(121-100)/100
=2000*21/100
=420
CI=Rs420

Answer 2

P=rs. 2000
R=10%
T=2yrs
For 1st yr:
I=prt/100
=2000x10x1/100
=rs. 200
For 2nd yr:
P=2000+200
=rs. 2200
Thus I=prt/100
=2200x10x1/100
=rs. 220
CI=200+220
=rs. 420 (ans.)