IBPS - QUANTITATIVE APTITUDE - PERCENTAGE

PERCENTAGE

Rule I

       First time x% is increased and second time x% is decreased, 

then loss% = 

Example 1

       The price of a book is decreased by 60%. After somedays decreased price is increased 60%. At last decrease or increase percent is :

  (1)  1%     (2) 0.36%    (3) 36%   (4) 0%   (5) None

Solution :    Loss%= Decrease % = = 36%.

Rule II

     (i) If P's salary is r% more than Q's then Q's salary less than

 P's= %

     (ii) If P's salary is r% less than Q's then Q's salary more than

 P's=%

Example 1

       If P's salary is 50% more than Q's, then how much percent is Q's salary less than P's ?

         (1) %   (2) 30%   (3) %   (4) %   (5) None

Solution :

    Q's salary less than  P's = % = %

Example 1

       If P's salary is 50% below Q's, then how much percent is Q's salary above P's ?

         (1) 0%   (2) %   (3) 50%  (4) 100%   (5) None

Solution :

    Q's salary above  P's =% = 100%

Rule III

        In price increasement of x%, reduce percent to have no extra

 expenditure= %

Example

         If the price of milk is increased by 1%, how much percent must a man reduce his consumption of milk to have no extra expenditure ?

  (1) %   (2) %   (3) %    (4) 1%    (5) None

Solution : Reduction percent = %= %

Rule IV

        In price decreasement of x%, increasement percent in consumption to maintain some expenditure= %

Example 

         The price of sugar is reduced by 40%. Find by how much percent must its consumption be increased so that the expenditure may be the same as before ?

(1) 45%    (2) %    (3) %   (4) %   (5) None

Solution :   Incresement Percent = % = = %

Rule V

        First time x% is increased and second time y% is increased, then 

Incresement in percent=

Example   

        The price of a T.V is increased 30% before budget  and in budget 20% is also increased. Then tolta, increasement in price will be:

(1) 50    (2) 56   (3) 55    (4) 59   (5) None

Solution:     Increase Percent = =50+6 =56.

Rule VI

      In decreasements are in x% and y% for a fixed price then, 

Reduction percent =

Example

      The price of commodity is reduced two times as 40% and 10% respectively. Then what is percentage decreasement in the price ?

(1) 48    (2) 46   (3) 45   (4) 51    (5) None

Solution :     Percentage decreasement = = 46.