Question

rita has pens and pencils which together are 40 in number. if she has 5 more pencils and 5 less pen, rhen the number of pencils would become 4 times the number of pens. find the original number of pens amd pencils.

Answer 1

Solution :
               Number of Pens and Pencils  = 40
               Let the number of  Pens = x
               and let Number of Pencils = y
             therefore ,
                             x + y = 40
                           => y = 40 - x ............................. (1)
According to Question ,
               y + 5 = 4 ( x - 5 )
               y +5 = 4*x - 4*5
              y + 5  = 4x - 20
               y = 4x -20 -5
               y = 4x - 25 ...................................(2)
         from 1 and 2 , we get
               4x - 25 = 40 - x 
               4x = 40 - x + 25
               4x + x = 40 + 25
               5x = 65
                 x = 65/5
                 x = 13

Therefore Number of Pens = 13
Substitute the value of x in 1 , we get
               y = 40 - x
               y = 40 - 13
               y = 27

Therefore Number of Pencils = 27

Hope this helps You!!!