Government Jobs in India 201718 Presented by GovtJobsPortal.IN. Daily 10 New Govt Jobs. Stay Tuned in with Us for latest jobs, Results and Study Material for Government Exam.
Concepts
of Percentage
Shared
by: WWW.GovtJobsPortal.IN
Definition of Per Cent:
A Fraction having Denominator 100 is called a Per Cent & is denoted by
symbol %.
# To convert
the Fraction into Percentage
To
convert a fraction into Percentage, multiply the fraction by 100 & put %
sign.
For
Eg: 4/5 à 4/5 * 100 =
80%
# To convert
Percentage into a Fraction
To
convert a percentage into a fraction replace the % sign with 1/100 & reduce
the fraction to simplest form.
For
Eg: 20% à 20/100 =
1/5
# To convert
Percentage into Ratio
To
convert a percentage into a ratio, first convert the given percentage into a
fraction in simplest form & then to a ratio.
For
Eg: 25% à 25/100 =
1/4 = 1 : 4
Important
Concepts:
1. 100% of a Number
= Number itself
For eg: 100% of 500 = 500
2. 50% of a number = Half of the number
For eg: 100% of 500 = 500
2. 50% of a number = Half of the number
For eg: 50% of 500 = 500/2 = 250
3. 25% of a number = Quarter(1/4th) of the number or Half of 50% of the number
3. 25% of a number = Quarter(1/4th) of the number or Half of 50% of the number
For eg: 25% of 500 will be 500/4 or 250/2= 125
4. To find the 1% of a number, shift the decimal point by 2 place to the left.
4. To find the 1% of a number, shift the decimal point by 2 place to the left.
For eg: 1% of 500 will be 5.00
5. To find the 10% of a number, shift the decimal point by 1 place to the left.
5. To find the 10% of a number, shift the decimal point by 1 place to the left.
For eg:10% of 500 = 50.0
6. 5% of the number is half of 10% of a number
6. 5% of the number is half of 10% of a number
For eg:5% of 500 = 50/2=25
7. 15% of the number = Sum of 10% and 5% of a number
7. 15% of the number = Sum of 10% and 5% of a number
For Eg: 15% of 500=(10% of 500)+(5% of 500=50 + 2 =75
Using the
above methods now we can find the percentage of a number easily:
Example: 15% of 400 = ?
Example: 15% of 400 = ?
Step 1: Split the
percentage term into 2 numbers that we can easily find the percentage of.
We can split 15% into
10% and 5%
Step 2: First find 10% of 400 by shifting the decimal point to the left by 1 place.
Step 2: First find 10% of 400 by shifting the decimal point to the left by 1 place.
i.e 10% of 400=40.0
Step 3: Now find 5% of 400 i.e half of 10%
Step 3: Now find 5% of 400 i.e half of 10%
i.e 5% of 400=40/2 = 20
Step 4: Now add both the results
Step 4: Now add both the results
we get, 15%+5%=40 + 20 =
60
Therefore, 15% of 400 = 60
Therefore, 15% of 400 = 60
Important
Formulas:
1)
Percentage
Increase/Decrease:
If the present value of a machine is P & it depreciates at the rate of R% per annum. Then:
·
If the price of a commodity increases by R%, then the reduction in
consumption so as not to increase the expenditure is:
= [(R/100+R) * 100]%
= [(R/100+R) * 100]%
·
If the price of a commodity decreases by R%, then the increase in
consumption so as not to decrease the expenditure is:
=[(R/100R) * 100]%
=[(R/100R) * 100]%
2)
Population:
If the Population of a town be P now & it increasing at the
rate of R% p.a, then,
·
Population after n years = P[1+(R/100)]^n
·
Population n years ago = P[1+(R/100)]^n
3) Results on Depreciation
If the present value of a machine is P & it depreciates at the rate of R% per annum. Then:
·
Value of the machine after n years= P[1(R/100)]^n
·
Value of the machine n years ago= P/[1(R/100)]^n
4)
If P is R% more than Q, then Q is less than A by
={ [R/(100+R)]*100}%
={ [R/(100+R)]*100}%
5)
If P is R% less than Q, then Q is more than A by
={ [R/(100R)]*100}%
={ [R/(100R)]*100}%
Learn the
Following Table for Fast calculations:
Fraction

Percentage

1/1

100%

1/2

50%

1/3

33.33%

1/4

25%

1/5

20%

1/6

16.66%

1/7

14.28%

1/8

12.5%

1/9

11.11%

1/10

10%

1/15

6.66%

1/20

5%

1/25

4%

1/30

3.33%

1/40

2.5%

1/50

2%

1/60

1.66%

1/75

1.33%

1/80

1.25%

1/90

1.11%

1/100

1%

By
Using this Conversion Table we can convert Fraction into Percentage and
Percentage into Fraction easily.
For Eg: To find 3/5 in %?
For Eg: To find 3/5 in %?
Solution:
As we have 1/5=20%
then, Multiply both
sides by 3
i.e 1/5x3 = 3x20%
Therefore, 3/5 = 60%.
RELATED JOBS
3 comments:
Post a Comment