Percentage shortcut tricks and concepts have become a mainstream solution for students who are preparing a government job. However, many students who are preparing a government job make a major mistake of not giving up attention on the basic concept. So I highly recommended you before reading type-3 you first read percentage type-1 and type-2. In percentage type-1 and percentage type -2 I have already discussed a basic concept of percentage, percentage shortcut tricks and an important percentage problem for exam point of view.
Now, percentage type-3, I have covered percentage shortcut tricks, concepts, and common type question that is frequently asked in various competitive exams like SSC CGL, SSC CHSL, BANK, RAILWAYS etc.
IMPORTANT PERCENTAGE SHORTCUT TRICKS,CONCEPTS AND PROBLEM FOR COMPETITIVE EXAM
FOR EXAMPLE
(Q1)Due to a decrease in price per kg. of sugar by 25% by how much percent, a housewife should increase quantity so that total expenditure remains same.
Solution:Let initial price=Rs. 100
Now,
% Increase=(25/75)×100
=33.33% Ans
Rough:New price=100×(100-25)/100
=Rs75
Concept:[जब Question में कहा जाए कि Total Expenditure same है तो आपलोगों को Quantity always price का reverse लेना है.
Explanation:[पहले housewife Rs 100 में 75 kg sugar खरीदती थी जब price decrease किया तो Rs 75में 100kg sugar खरीदती है तो इस तरह से housewife 25 kg अधिक sugar खरीद पा रही है ]
BY TRICK:
% increase=(25/100−25)×100
=(25/75)×100
=33.33% Ans.
(Q2)Due to increase in price per kg of sugar by 25% by how much percent, a housewife should decrease quantity so that total expenditure remains same.
Solution:Let initial price=Rs100
Now,
%decrease= (25/125)×100
=20% Ans
Rough:New price=100×(100+25)/100
=Rs125
BY TRICK:
%Decrease=(25/100+25)×100
=(25/125)×100
=20% Ans.
(Q3)If the price of sugar rises from Rs 6 per kg to Rs 7.50 per kg, a person to have no increase in his expenditure on sugar, will have to reduce his consumption of sugar by:
Solution:
% Reduce=(1.50/7.50)×100
=20% Ans
(Q4)The length of the rectangle is increased by 60%.By what percent would the breadth be decreased to maintain the same area?
Solution:Area of rectangle=Length×Breadth
Let initial length=100
% Decrease=(60/160)×100
=37½% Ans.
Concept:Breadth, Length का reverse लिया गया है because Area is same.
BY TRICK:
% Decrease=(60/100+60)×100
=(60/160)×100
=37½% Ans.
(Q5)One side of a square is increased by 30%.To maintain the same area,the other side will have to be decreased by.
Solution:Area of square=Side×Side
Let initial length of side=100
Now,
% Decrease=(30/130)×100
=23¹/3% Ans.
BY TRICK:
% Decrease=(30/100+30)×100
=23¹/3% Ans.
(Q6)The height of a triangle is increased by 10% to retain the original area of the triangle,its corresponding base must be decreased by:
Solution:Area of Triangle=½×base×height
Let initial height=100
%Decrease=(10/110)×100
=9¹/11% Ans.
BY TRICK:
%Decrease=(10/100+10)×100
=(10/110)×100
=9¹/11% Ans
If you have any queries regarding this topic feel free to ask me in the comments below.
Did you like this article? Share it with your friends on Facebook, Twitter,WhatsApp and Google Plus!
Nice trick