Question

If the cost of two books and five pens is 225rs. And the cos of four pen and three books is rs 320. Then what is the cost of one pen

Answer 1

let book=x and pen=y

then,    2x+5y=225 .................(1)

           3x+4y=320  .................(2)

multiply eq.1 by 4 and eq. 2 by 5.

so   8x+20y=900

     15x+20y=1600

subtract

-7x = -7oo

7x = 700

x = 100

put value of x in eq. 1

 2(100)+5y=225

5y= 225-200

y=5

hence book= 100Rs

pen= 5Rs

     

Answer 2

The cost of the one pen is 5..

                Thanku