PERCENTAGE math capsule
I was always the first kid in my classroom to whom the teacher used to ask what percentage of studies do you do at home?
And i was confused every time, why because i did not know the answer? Not really , i knew it .... but the answer was 0% .
hehe
But yeah of course i used to cover all this during the school hours of mine ,
so , lets start this blog post and i hope this will help you guys learn at a much faster rate.
PER CENT
Per cent is a fraction whose denominator is 100 and numerator of the fraction is called the rate per cent . Per cent is denoted by the symbol '%'.
RULES AND FORMULAE
RULE 1
For expressing a % as a fraction then a% = a / 100 , i.e. divide 'a' by 100 and reduce it to the lowest form .
e.g. 25 % = 25 / 100 = 1 / 4
RULE 2
For expressing a fraction a / b as a percent . Then ,
a / b = {( a / b )* 100 } %
e.g. 2 / 3 ={(2 / 3 )* 100} % = 200 / 3 %
RULE 3
To find how much per cent one quantity is of another quantity ?
Required percentage = (First quantity / Second quantity) * 100 %
RULE 4
Percentage increase or decrease in a value .
Increase or decrease percentage = (Increase or decrease in the value / Initial value) * 100 %
RULE 5
If A's income is X% more than that of 'B', then B's income would be [x / (100+x)]*100 % less than that of 'A'.
RULE 6
If 'A' income is x% less than that of 'B' then B's income is would be [x / (100 - x)]* 100 % more than that of A.
RULE 7
If the price of a commodity is increased or decreased by x% then the decrease or increase in consumption so as not to increase or decrease the expenditure is [x / (100 + x)] * 100 %
easy? just a few more points to remember ,
POINTS YOU NEED TO REMEMBER
(1) If the value of number is first increased by x % and later decrease by x%, then there is always a decrease in number. This decrease is equal to x² / 100 % or (x / 10)² %.
(2) If the value of an object is first changed (increased or decreased) by x% and then changed (increased or decreased ) by y % , then
Net effect = [± x ± y ± {(±x)*(±y)} / 100]* 100 %
here , + sign is used in one of increase and - sign is used in case of decrease.
(3) In an examination x % of total number of students failed in a subject A and y% of total number of students failed in subject B and z% failed in both the given subject then percentage of students who passed in both the subject is [100 - (x + y - z)] %.
Lets do some exercises now!
'Practise makes a man perfect'
:)
MATH CAPSULE PRECENTAGE 1 |
MATH CAPSULE PERCENTAGE 2 |
MATH CAPSULE PERCENTAGE 3 |
MATH CAPSULE PERCENTAGE 4 |
MATH CAPSULE PERCENTAGE 5 |
MATH CAPSULE PERCENTAGE 6 |
THANK YOU FOR READING THIS AT MATH CAPSULE
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