# S.I. & C.I. (7)

1. A sum was put a simple interest at a certain rate for 2 years. Had it been put at 4% higher rate, it would have fetched Rs. 60 more. The sum is:
1. Rs.750
2. Rs.700
3. Rs.820
4. Rs.940

Explanation :-

Let the sum be Rs.x  & the initial rate be R%.
Therefore,
[(x*(R+4)*2)/100] – [(x*R*2) /100] = 60
2xR + 8x – 2xR = 6000
8x = 6000
x=  Rs.750

2. The simple interest at x% for x years will be Rs. x on a sum of:
1. Rs. x
2. Rs. x/2
3. Rs. 100/x
4. Rs. 100x/2

Explanation :-

P = ?,    R = x%,    SI = x,    T = x years
P=(SI*100)/(R*T)=(x*100)/(x*x)
P=100/x

3. A sum of money becomes 7⁄5 of itself in 4 years at a certain rate of simple interest. The rate per annum is :
1. 9%
2. 10%
3. 11%
4. 12%

Explanation :-

Lets suppose  the sum of money be Rs.x ,    T = 4 years  ,    R = ?
Amount After 4 years
SI = [(7/5)x]-x = (2x)/5
R = (SI*100)/(P*T)
R = [(2x/5)*100]/(x*4) = 10%

4. If the simple interest on Rs. 2000 is less than the Simple Interest on Rs. 3000 at 5% by Rs. 50, find the time.
1. 2.5 year
2. 1 year
3. 1.5 year
4. 2 year

Explanation :-

Difference in principal = 3000-2000 = 1000
Therefore,
SI on Rs.1000 = Rs.50
[(1000*5*T)/100] = 50
50T=50
T = 1 Year

5. A sum of Rs. 7700 is to be divided among three brothers Vikas, Vijay and Viraj in such a way that simple interest on each part at 5% per annum after 1, 2 and 3 years respectively remains equal. The Share of Vikas is more than that of Viraj by
1. Rs.1200
2. Rs.1400
3. Rs.2200
4. Rs.2800