Percentages Concepts and Formulae

Percentage means out of 100. We can easily convert any fractional and decimal value into the percentage. The percentage is a very important topic for Bank PO, Bank Clerk, SSC, Railways etc.
The percentage is also a very important topic for Data interpretation, Simplification and for other Quants Arithmetic topics.

Convert Decimal value into Percentage:

To convert decimal value into percentile value simply multiple the decimal numbers by 100 and it will be converted into percentile value.
Examples:1. Convert 0.65 into percentage0.65 100 = 65%
2. Convert 4.05 into percentage4.05 100 = 405%


Convert fractional value into Percentage

To convert fractional value into percentile value multiply fractional by 100 and then convert it into lowest fractional form or decimal form.
Examples:1. Convert into percentage 100 = ( 3 5) % = 15%
2. Convert into percentage 100 = (8 4) % = 32 %

Basic conversion of fraction to percentage to remember:

= 100 %

= 50 %

= 33.33 % = 33

= 25 %

= 20 %

= 16.67 %

= 14.28 %

= 12.5 %

= 11.11 % = 11

= 10 %

= 9.09 %

= 8.33 %

= 7.69 %

= 7.14 %

= 6.67 %

= 6.25 %

= 5.88 %

= 5.55 %

= 5.26 %

= 5 %


If we remember the above easy conversions then we can convert some more fractions into percentage easily
Example:We remember than percentage of (1/16) is 6.25%
Then we can easily find conversions of 2/16, 3/16, 4/16, 5/16, ……… 16/16 as
= 5 = 5 6.25 = 31.25 %
= 7 = 7 6.25 = 43.75 %
= 13 = 13 6.25 = 81.25 %
= 12.5 %

So we can find easily percentage for 2/8, 3/8, 4/8, 5/8, 6/8, 7/8, 8/82/8 = (2 12.5) % = 25 %
= (3 12.5) % = 37.5 %
= (4 12.5) % = 50 %
= (5 12.5) % = 62.5 %
= (6 12.5) % = 75 %
= (7 12.5) % = 87.5 %
= (8 12.5) % = 100 %

Percentage of Some Difficult Fractions

If numerator < denominator, the percentage will always be less than 100%
If numerator > denominator, the percentage will always be greater than 100%

1.

Step 1: 

Take 10% of the denominator and find the closest multiple to the numerator and less than numerator
i.e. 10 % of 600 = 60
60 8 = 480
Hence the percentage will be greater than 80% and less than 90 %

Step 2: 

Subtract the highest multiple (480) from numerator (512)
512 – 480 = 32

Step 3: 

Take 1% of the denominator and find the closest multiple to the subtracted result of Step 2 (i.e. 32)
i.e. 1 % of 600 = 6
6 5 = 30
Hence the percentage will be greater than 85 % and less than 86 %

Step 4: 

Subtract the multiple (30) from resultant (32)
i.e. 32 – 30 = 2

Step 5: 

Take 0.1% of the denominator and find the closest multiple to the resultant of Step 4
i.e. 0.1 % of 600 = 0.6
0.6 3 = 1.8
Hence the percentage will be greater than 85.3 % and less than 85.4 %
Keep repeating the steps if further required

2. 

Numerator > Denominator then percentage greater than 100%

Step 1: 

10 % of 560 = 56
56 11 = 616
Hence percentage is greater than 110% and less than 120%

Step 2: 

640 – 616 = 24

Step 3: 

1 % of 560 = 5.6
5.6 4 = 22.4
Hence percentage is greater than 114% and less than 115%

Step 4: 

24 – 22.4 = 1.6

Step 5: 

0.1% of 560 = 0.56
0.56 2 = 1.12
Hence percentage is little bit greater than 114.2%
We can solve any fraction through this process

TRY OUT SOME EXAMPLES
1214/1560, 295/340 , 783/260 , 951/800

Suggested Books: View here
Percentages Concepts and Formulae Percentages Concepts and Formulae Reviewed by Jasleen Behl on Friday, April 04, 2014 Rating: 5

No comments:

I will try to respond asap