Lesson18

 

Percentage

   You can find percentage very fast, no calculations,  write only required answer  directly 
 
     10 %   :  Just divide the number by 10                         Find 10% of 229   = 229/10 =22.9
     12.5%:   Just divide the number  by   8                        Find 12.5%  of 208 = 208/8 =26
     33  1%  :   Just divide   the number by 3                         Find      331%   of    270  =   270 /3 =90               
         3                                                                                           3

    25%      Just divide  the  number by  4                          Find  25% of 296        = 296/4 =74
    50%      Just divide the number   by  2                          Find 50% of 296        =296/2   148
    75%:     Just divide the number  by  3/4                        Find 75%  of 208 = 208x3/4 =624/4=156
    37.5%Just divide   the number by 3/8                        Find 37.5% of    240  =   240x3 /8  =90
    15%       Just multiply by 3 and divide by 20                 Find 15% of 296  = 296x3/20 =888/20=44.4
                    and put proper decimal   
    45 %     Just  multiply by 9 and divide by 20                 Find 45% of 122 = 122x9/2   = 1098 =54.9
                       and put proper decimal                             Hint   use multiplication by 9  Lesson 5
    55%       Just multiply by 11 and divide by 20              Find 55 % of 132 = 232 x11/20 = 2553/20=127.65
                        and put proper decimal                            Hint   use multiplication by 11  Lesson 2( By using
                                                                                              same method we can calculate %of 35  ,85 ,95)
  10.25%   Calculate   in two parts  10% & .25%             Find 10.25% of 240   :  10% of 240 + .25 % of 240
                                                                                                                              =   240/10   +240/400
                                                                                                                              = 25           +.6
                                                                                                                              =  24.60
   25.25.%   Calculate in two parts 25 % & .25%               Find 25.25%of 280     :    25%of 280 +  .25%of 280
                                                                                                                               =   280/4    +  280/400
                                                                                                                               =   70 + .7
                                                                                                                               =   70.7        

  56%   Calculate in two parts  55%&1%                           Find 56% of 780           55%of 780 +1 %of 780
                                                                                                                              =  780x11/20 +780/100
                                                                                                                              =  39x11        +7.8
                                                                                                                              =    429         +7.8
                                                                                                                              =   436.7

  78% calculate in two parts  80%-2%                             Find 78% of 1640           80 %of 1640    -2%of 1640
                                                                                                                            =  1640x8/10    -1640x2/100
                                                                                                                            = 1312              -32.8
                                                                                                                            = 1279.2

12%   Calculate in two parts 10 %+2%                           Find 12 %of 268               26.8 +5.36  =32.16

 26%   Calculate in two parts 25%+1%                           Find 26 %of 292              292/4 + 2.92  =73+2.92
                                                                                                                                =75.92
89 %  Calculate in two parts  100%-11%                        Find 89 % of 256             256  - 11x256/100 =256 -28.16
                                                                                                                                =227.84

    Apply little presence of mind and calculate percentage as fast as you can.


 

                                                                                                 

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