Principal: The money borrowed or lent out for a certain period is called the principal or the sum.
Interest: Extra money paid for using other’s money is called interest.
Simple Interest (SI): If the interest on a sum borrowed for certain period is reckoned uniformly, then it is called simple interest.
Rate= R% per annum(p.a)
Time= T years
(i) Simple Interest ( SI )= (P×R×T)/100
P = (100×SI) /(R×T)
R= (100×SI) /(P×T)
T= (100×SI) /(P×R)