1. What is the present worth of Rs. 132 due in 2 years at 5% simple interest per annum ?
Let the present worth be Rs.x Then, S.I.= Rs.(132 - x) =› (x*5*2/100) = 132 - x =› 10x = 13200 - 100x =› 110x = 13200 x= 120 2. Find the rate at Simple interest, at which a sum becomes four times of itself in 15 years.
Let sum be x and rate be r% then, (x*r*15)/100 = 3x [important to note here is that simple interest will be 3x not 4x, because 3x+x = 4x] => r = 20%
3. Effective annual rate of interest corresponding to nominal rate of 6% per annum compounded half yearly will be ?
Let the amount Rs 100 for 1 year when compounded half yearly, n = 2, Rate = 6/2 = 3% Amount=100(1+3100)2=106.09 Effective rate = (106.09 - 100)% = 6.09%
.4 A sum of money invested at compound interest to Rs. 800 in 3 years and to Rs 840 in 4 years. The rate on interest per annum is. S.I. on Rs 800 for 1 year = 40 Rate = (100*40)/(800*1) = 5% 5. Principal: 'P' = Rs. 50,000, Interest rate: 'R' = 10% = 0.10, Repayment time: T = 3 years. Find the amount of interest paid.