Question

A person spent rupees 564 in buying pens and pencils if cost of each pen is rupees 7 and each pencil is rupees 3 and if total number of things bought was 108 how many of each type did he buy

Answer 1

Answer:

Explanation:number of pencils bought be x.

number of pens bought be y.

therefore, money spend on pencils= 3x Rs

money spend on pens= 7y Rs

Given, total no. of items bought= 108

Therefore, x+y=108     (i)            

Total money spent= 564 Rs

Therefore, 3x+7y= 564     (ii)

Multiply equation (i) with 3,

=>3x+3y=324  

Subtract equation (i) from equation (ii): (3x+7y)-(3x+3y)

ie, 3x+7y=564

    -3x-3y=-324

      _________

               4y=240

Therefore, y=60 ( from the above equation)

then, x = 108- 60=48 ( as x+y= 108)

Therefore, pens bought= 60 and pencils bought= 48