3
Q:

# The difference between the compound interest and simple interest on a certain sum at 10% per annum for 2 years is Rs. 631. Find the sum.

 A) 60100 B) 61100 C) 62100 D) 63100

Explanation:

Let the sum be Rs. x. Then,
C.I. = x ( 1 + ( 10 /100 ))^2 - x = 21x / 100 ,
S.I. = (( x * 10 * 2) / 100) = x / 5
(C.I) - (S.I) = ((21x / 100 ) - (x / 5 )) = x / 100
( x / 100 ) = 632 * x = 63100.
Hence, the sum is Rs.63,100.

Q:

Simple interest on a certain sum at 7% per annum for 4 years is Rs. 2415. What will be the compound interest on the same principal at 4% per annum in two years?

 A) Rs. 704 B) Rs. 854 C) Rs. 893 D) Rs. 914

Explanation:

We know that,

From given data, P = Rs. 8625

Now, C.I  =

2 178
Q:

Find the compound interest on Rs. 6,500 for 4 years if the rate of interest is 10% p.a. for the first 2 years and 20% per annum for the next 2 years?

 A) Rs. 3845 B) Rs. 4826 C) Rs. 5142 D) Rs. 4415

Explanation:

We know the formula for calculating

The compound interest  where P = amount, r = rate of interest, n = time

Here P = 5000, r1 = 10, r2 = 20

Then

C = Rs. 4826.

5 129
Q:

What is the difference between the compound interests on Rs. 5000 for 11⁄2 years at 4% per annum compounded yearly and half-yearly?

 A) Rs. 1.80 B) Rs. 2.04 C) Rs. 3.18 D) Rs. 4.15

Explanation:

Compound Interest for 1 12 years when interest is compounded yearly = Rs.(5304 - 5000)

Amount after 112 years when interest is compounded half-yearly

Compound Interest for 1 12 years when interest is compounded half-yearly = Rs.(5306.04 - 5000)

Difference in the compound interests = (5306.04 - 5000) - (5304 - 5000)= 5306.04 - 5304 = Rs. 2.04

4 207
Q:

The difference between simple interest and compound interest of a certain sum of money at 20% per annum for 2 years is Rs. 56. Then the sum is :

 A) Rs. 3680 B) Rs. 2650 C) Rs. 1400 D) Rs. 1170

Explanation:

We know thatThe Difference between Compound Interest and Simple Interest for n years at R rate of interest is given by

Here n = 2 years, R = 20%, C.I - S.I = 56

8 217
Q:

Find the compound interest on Rs. 2680 at 8% per annum for 2 years ?

 A) Rs. 664.21 B) Rs. 548.68 C) Rs. 445.95 D) Rs. 692.57

Explanation:

We know Compound Interest = C.I. = P1+r100t - 1

Here P = 2680, r = 8 and t = 2

C.I. = 26801 + 81002-1= 268027252-12= 26802725+12725-1= 2680 5225×225

= (2680 x 52 x 2)/625

= 445.95

Compound Interest = Rs. 445.95

9 265
Q:

The compound interest on Rs. 8000 for 3 year at 10% p.a. is

 A) 2648 B) 2145 C) 2587 D) 2784

Explanation:

8000 × 33.1% = 2648

11 445
Q:

Compound interest on a certain sum of money at 20% per annum for 2 years is Rs.5995. What is the SI on the same money at 8% per annum for 6 years ?

 A) Rs. 5989 B) Rs. 6540 C) Rs. 7844 D) Rs. 6789

Explanation:

Given C.I = 5984, R = 20% , T = 2yrs

5984 = $\inline \fn_jvn \small C.I=P\left [ \left ( 1&amp;plus;\left ( \frac{20}{100}\right )^{2} \right )-1 \right ]$

=> P = (5995x25)/11

P = Rs. 13625

Now S.I = PTR/100

SI = (13625 x 8 x 6)/100 = Rs. 6540

19 1387
Q:

At a certain rate of interest the compound interest of 3 years and simple interest of 5 years for certain sum of money is respectively Rs. 1513.2 and Rs. 2400. Find the common rate of interest per annum ?

 A) 5% B) 6% C) 4% D) 3%

Explanation:

Given compound interest for 3 years = Rs. 1513.2

and simple interest for 5 years = Rs. 2400

Now, we know that  C.I =

=> 1513.2 =  ...........(A)

And S.I = PTR/100

=> 2400 = P5R/100 ..................(B)

By solving (A) & (B), we get

R = 5%.