How much time will it take for an amount of 450 to yield 81 as interest at 4.5% per annum of simple interest?  Choose the correct answer.
A) 5 years  B) 8 years  C) 2 years  D) 4 years  E) 9 years
4 years   4 years   Time = (100 x 81)/(450 x 4.5) years = 4 years.
<result>D</result>
How much time will it take for an amount of 450 to yield 81 as interest at 4.5% per annum of simple interest?