How much time will it take for an amount of Rs. 900 to yield Rs. 81 as interest at 4.5% per annum of simple interest?

A. 2 years
B. 3 years
C. 1 year
D. 4 years
P = Rs.900
SI = Rs.81
T = ?
R = 4.5%
T=100×SI/PR =100*81/900*4.5 =2 years