Question

The total cost of 6 pens and 4 pencils is Rs. The total cost of 4 pens and 6 pencils is Rs. If so, calculate the cost of a pen and a pencil.​

Answer 1

Let the cost of a pen and a pencil be x and y respectively.

4x+4y=100

x+y=25 ...(1)

3x=y+15

3x−y=15 ...(2)

Adding (1) and (2), we get

4x=40

x=10

Substitute x=10 in equation (1) to get y=15.