Quantitative Aptitude Simple Interest Study Material
1. ‘Interest’ is the money paid by a borrower to the fender for die use of money borrowed.
2. The money borrowed or lent out for a certain period is called the ‘Principal’ or ‘ the sum ‘.
3. The sum of Interest and Principal is called the Amount
Thus Amount = Principal + Interest
4. The duration of period for which the money is borrowed is called the Time.
5. The interest is charged according to some pre condition which is expressed in general as a rate per cent of the principal for each year and is called Tate percent per annum. Thus if the rate of interest is 5% per annum, it means that the interest on principal of Rs. 100 for one year is Rs. 5.
Here ‘per annum’ means ‘for a year’.
6. If throughout the loan period, the interest is charged on the original sum (Principal) borrowed, it is called Simple Interest.
7. Some abbreviations to be used frequently : .
P = Principal . R = Rate of interest .
T = Time S.I. = Simple interest
A = Amount
9. .one ordinary year is equal to three hundred and sixty five days.
10. .one leap year is equal to three hundred and sixty six days
11. .the number of days in February of leap year is twenty nine.
12. . If the rate per cent is given half years or quarterly then to find the rate pet cent per annum mutliply by two or four respectively.
13. . In counting the number of days between the two given dates the entire day Is excluded. You have to keep in my that interest. Is not charged for the day on which money is borrowed but it is charged for the day it is returned