**The Simple interest on a certain sum for 2 years at 10% per annum is Rs. 90. The corresponding compound interest is:**

A.97

B.90

C.94.50

D.100

Answer

Option (c) is correct

**Explanation:**

Sum = (100 x90)/(2×10) = Rs. 450

C.I. =

**Manoj borrowed a certain sum from Anuj at a certain rate of simple interest for 2 years. He lent this sum to Rakesh at the same rate of interest compounded annually for the same period. At the end of two years, he received Rs. 4200 as compound interest but paid Rs. 4000 only as simple interest. Find the rate of interest?**

A.10%

B.20%

C.25%

D.30%

Answer

Option (a) is correct

**Explanation –**

Suppose the sum borrowed = Rs X

Rate of interest = R%, Time = 2 years

4000=(x * R * 2) /(100) [simple interesr formula]

RX=200,000………….(1)

Amount=

after solving and using value of RX

we get R=10%

**If the difference between the simple interest and compound interests on some principal amount at 20% for 3 years is Rs. 48, then the principal amount is**

A.636

B.650

C.375

D.400

Answer

Option (c) is correct

**Explanation –**

For three years

= Rs. 375

**What sum invested for 2 years at 12% compounded annually will grow to Rs. 4390.40…..**

A.4000

B.3875

C.3800

D.3500

Answer

Option (d) is correct

**Explanation –**

P=3500

**A sum of money is borrowed and paid back in two annual installments of Rs. 882 each allowing 5% compound interest. The sum borrowed was:**

A.1620

B.1640

C.1680

D.1700

Answer

Option (b) is correct

**Explanation –**

= (882 x (20/21))+ (882 x (400/441))

= Rs. 1640

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