PERCENTAGE
CHAPTER MATHS TRICKS
Basically on previous article we provide the profit and loss and work and time
tricks now, we are provide percentage chapter of maths that is very useful in all exams
and 8-10 no. of question are asked from that chapter.
With the help of percentage tricks we can apply is to the various form like
ratio, profit loss, time and distance, graphs, pie chart etc these are
basically are the form of percentage and if you clear the basic concept it will
be beneficial in many ways.
so, first what is percentage
DEFINITION
a percentage is a number or ratio expressed as a fraction of
100.
if we have to convert percentage into fraction than it is divide by
100.
Example
1 :- if
we write 45% then its equal to 45/100 or in fraction 9/20 or in decimal 0.45
if we have to convert fraction into percentage we have to multiple
with 100.
Example 2 :- if we write
3/5 in fraction it is equal to 60%
3/5x100=60.
READ AND LEARN FOLLOWING TABLE as
also known as conversion table of percentage. Learn this table it help you a
lot to solve many problem.
the following fraction in red colour are MOST IMPORTANT.
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 this conversion table we can change fraction into percentage and
percentage into fraction
EX:- if we have to find 2/5 in %?
In the
table we know that 1/5=20%
then, if we multiply both by 2
then we have 1/5x2 = 2x20%
answer is
2/5 = 40%
so, you only to know basic fraction and percentage that given above.
in the inverse
Ex. If we have to find out 1/15 fraction in percentage%?
In the
table we have 1/5 = 20%
then
both side multiple by 1/3
we get
1/15 = 6.66%
SOME BASIC QUESTION THAT IS ALWAYS ASKED IN THE EXAMS
TYPE 1.
if there is increase of X% and subsequently X% decrease then there is always
loss / decrease in the condition.
ex. If rohan salary is increase by 50% and subsequently decrease by 50%. How
much percentage loss?
ans. By trick ---- 50x50/100= 25% decrease/loss
TYPE 2.
if A is P% more than B. then B is less than by A
with P/(100+P)x100
ex. If radha earning is 25% more than sita. Then sita earning is how many
percentage less then by radha?ans. By trick ---- 25/(100+25)x100=20%
TYPE 3.
If A is
P% less than B. then B is more than by A
with P/(100-P)x100
ex. If golu age is 20% less than gita than gita age is how many percentage more
than golu?
ans. By trick ---- 20/(100-20)x100=25%
TYPE 4.
if there is p% increase in price . how much % decrease his consumption so that
his expenditure on it does not change.
formula P/(100+P)x100
ex. If
petrol price increase by 25%. How much percentage a person reduced his
consumption so that his expenditure on it does not increase?
ans. 25/(100+25)x100=20%
TYPE 5.
if there is p% decrease in price . how much % increase his consumption so that
his expenditure on it does not change.
formula P/(100-P)x100
ex. If
there is 30% decrease in eggs price. How much a person increased his
consumption so that his expenditure on it does not increase?
ans. 30/(100-30)x100=42.85
TYPE 6.
Ex. If
suman need 36% minimum mark to passed a exam but she score 24% mark and fail by
9 marks. What is the total mark?
ans. Difference in % = difference in mark
In that
36%-24%=12%
that is 12%=9marks
so, total mark = 9/12x100= 75
Courtesy : http://www.questionpaper4exam.com/
