Trending

Worked Out Problem Simple Interest and Compound Interest

Jan 25 • Bank, Maths Notes • 4419 Views • No Comments on Worked Out Problem Simple Interest and Compound Interest

Worked Out Problem Simple Interest and Compound Interest

Worked Out Problem Simple Interest and Compound Interest for SSC,SBI PO,IBPS PO and government exam.

1. A  sum of Rs. 1600 gives a simple interest of Rs. 252 in 2 years and 3 months. the rate of interest per annum is

Solution: I =P × R × T/100

252 = 1600 × R × 9/4 /100

R = 7%

1. What sum of money will amount to Rs. 520 in 5 years and to Rs. 568 in 7 years at simple Interest ?

Solution: principal + interest for 5 years = 520                                                (1)

Principal + interest for 7 years = 568                                                                    (2)

Subtracting (1) from (2)

Interest for two years = 568 – 520 = 48

Interest for 1 years = 24

Interest for 5 years = 120

Principal = 520 – 120 = 400

1. What should be the least number of years in which the simple interest on Rs. 2600 at 6 2/3 % will be an exact number of rupees ?

Solution : Interest for 1 year = 26002031100 = 520/3

If we multiply by 3 in interest for 1 year, we get the exact number of rupees

Minimum time = 3 years

Best SSC Coaching Center in Gurgaon

1. Ratio of the principal and the amount after 1 year is 10 :12 . then the rate of interest  per  annum is

Solution: P:A = 10 :12

P : I = 10 :2

P/I = 10/2 = 5

I = P × R × T/100

I = 5I × R × T/100

R= 20%

Worked Out Problem Simple Interest and Compound Interest

1. A person invests money in three different schemes for 6 years, 10 years and 12 years at 10 percent,12 percent and 15 percent respectively. At the completion of each scheme, he gets the same interest. The ratio of his investment is

Solution: let the principal be P1,P2 and P3 for 6 , 10 and 12 years respectively

P1 = 100 × I/6 × 10

P2 = 100 × I/10 × 12

P3 = 100 × I/12 × 15

P1:P2:P3 = 1/60:1/120:1/180
= 6:3:2

Best Books for Competitive exam Preparation

1. The sum of money that yields a compound interest of Rs. 420 during the second year at  5% p.a. Is

Solution: C.I. = P [(1 + R/100)t-1] – PR/100

420 = P [(1+ 5/100)2-1] – P5/100

420 = 41P/400 – 5P/100

420 = 21P/400

P = 8000

For Join Best Exam Preparation group on Telegram

1. A man saves Rs. 2000 at the end of each year and invests the money at 5 Compound interest. At the end of 3 years he will have

Solution: he saves 2000 at the end of 1st year

Interest in the  second year = 2000 × 5 × 1/100 = 100

Amount = 2000 + 100 = 2100

He saves another 2000 at the end of 2nd year

Principal for the 3rd year = 2100 + 2000 = 4100

Interest in the 3rd year = 4100 × 5 × 1/100 = 205

Amount = 4100 + 205 = 4305

But he saves 2000 at the end of 3rd year

So total amount = 4305 + 2000 = 6305

This Question asked by Best Bank Coaching

1. The difference between the compound interest and simple interest for the amount Rs. 5000 in 2 years is Rs. 32. The rate of interest is

Solution: simple interest for 1st year = 5000R1/100 = 50R

Simple interest for 2nd year = 50R

Compound interest for 2nd year = 50R +50RR/100

Difference between C.I. and S.I. = 32

50R2/100 = 32

R2 = 64

R = 8%

Alternative

Difference between C.I. and S.I. = P R2/100100

32 = 5000 R2/10000

R2= 64

R = 8

1. A sum of money doubles itself in 4 years at compound interest. It will amount to 8 Times it self at the same rate of interest in :

Solution: let the principal be x

Amount = 2x in 4 years

2x = x(1r/100)4

2 = (1 + r/100)4

When amount = 8x

8x =  x(1 + r/100)t

8 =  (1r/100)t

23 = (1 + r/100)t

(1 + r/.100)12 = (1 + r/100)t

T = 12 years

1. If the compound interest on a certain sum for 2 years at 3% per annum is Rs. 101.50 , then the simple interest on the same sum at the same rate and for the Same time will be

Solution: The compound interest for 2 years in terms of interest is

C.I. = I +  I × r/100*2

101.5 = y + 3y/200

203y/200 = 101.5

Y = 20300/203
Y = 100

1.  An amount of money appreciates to Rs. 7000 after 4 years and to Rs. 10000 After 8 years at a certain compound interest compounded annually. The Initial amount of money was

Solution: After 4 years the amount 7000 will be the principal for the next 4 years

10000 = 7000 (1 + r/100)4

10/7 = (1 + r/100)4

Now, when amount =  7000, T= 4 years,

7000 = P(1 + r/100)4

7000 = P × 10/7

P = 4900

For Practice Question on Simple Interest and Compound Interest