Question

A student bought some pens at 8 each and some pencils at 31.50 each. If the total

number of pens and pencils purchased is 16 and their total cost is 50, how many pens
did he buy?
be
as his​

Answer 1

Explanation:

Letthenumberofpensbexand

numberofpencilsbey

then

x+y=16ory=16−x

andtheirvalue

8x+1.5y=50

8x+(

2

3

)(16−x)=50

8x+24−(

2

3

)x=50

8x−(

2

3

)x=50−24

(

2

13x

)=26∴x=4

theny=16−x=16−4=12