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 = 100×8020×2 = Rs. 200

Amount after 2 year on Rs.200 at 20% p.a( compounded annually) =P(1+R100)T

Amount = 200(1+20/100)^2

Amount = 200(120/100)^2 = (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)^2 = 882P(105/100)^2= 882

P(21/20)2 = 882

P = (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)^1 + 882/(1+5/100)^2

Sum = 882/(105/100 ) + 882/(105/100)^2

Sum = 882/(21/20) + 882/(21/20)^2

Sum = [(882×20)/21] + [(882×20×20)/(21×21)]

Sum =(42×20) + (42×20×20/21)1640

i.e., The sum borrowed = Rs.1640