# S.I. & C.I. (16)

1. The Simple interest on a certain sum for 2 years at 20% per annum is Rs. 80. The corresponding compound interest is
1. Rs. 66
2. Rs. 82
3. Rs. 86
4. Rs. 88

Answer & Explanation

Answer:- 4

Explanation :-

Principal, P = (SI×100)/ RT 100×8020×Rs. 200
Amount after 2 year on Rs.200 at 20% p.a( compounded annually) =P(1+R100)T
Amount = 200(1+20/100)^
Amount = 200(120/100)^= (200×120×120)/(100×100)
Amount 2×120×120/100 2×12×12 Rs. 288
Compound Interest = 288 – 200 = Rs.88

2. The Compound interest on Rs. 20,480 at 6 1⁄4 % per annum for 2 years 73 days, is :
1. Rs. 2929
2. Rs. 2219
3. Rs. 3021
4. Rs. 3049

Answer & Explanation

Answer:- 1

Explanation :-

3. A sum amounts to Rs. 882 in 2 years at 5% compound interest. The sum is
1. Rs. 800
2. Rs. 822
3. Rs. 840
4. Rs. 816

Answer & Explanation

Answer:- 1

Explanation :-

Amount After 2 years = Rs.882
Amount after 2 years = P(1+R100)T = 882
P(1+5/100)^= 882P(105/100)^2= 882
P(21/20)882
= (882×20×20)/(21×21) 2×20×20 Rs. 800

4. A sum put out at 4% compound interest payable half-yearly amounts to Rs. 13265.10 in 11⁄2 years. The sum is
1. Rs. 12500
2. Rs. 11200
3. Rs. 8840
4. Rs. 12600

Answer & Explanation

Answer:- 1

Explanation :-

5. A sum of money is borrowed and paid back in two annual instalments of Rs. 882 each allowing 5% compound interest. The sum borrowed was:
1. Rs.1820
2. Rs.1640
3. Rs.1260
4. Rs.1440

Answer & Explanation

Answer:- 2

Explanation :-

Present Worth = x / (1+R/100)^T
The sum borrowed = Present Worth of Rs.882 due 1 year hence + Present Worth of Rs.882 due 2 year hence
Sum = 882/(1+5/100)^882/(1+5/100)^2
Sum 882/(105/100 882/(105/100)^2
Sum 882/(21/20882/(21/20)^
Sum = [(882×20)/21] + [(882×20×20)/(21×21)]
Sum =(42×20) + (42×20×20/21)1640
i.e., The sum borrowed = Rs.1640