Two students are going to the store to buy school supplies for the new school year. One of the students buys 2 packs of pencils and 3 packs of pens for $8.25. Her friend purchases 5 packs of pencils and 2 packs of pens for $11.00. Is there enough information to determine the cost of 1 pack of pencils and 1 pack of pens? If so, find the cost of each. Explain your thinking.

Respuesta :

Let the unit price for pencil be x

Let the unit price for pack be y

   

If the students bought 3 packs of pencil and 2 packs of pen for $8.25, then;

[tex]2x+3y=8.25.... 1[/tex]

Similarly;

If her friend bought 5 packs of pencil and 2 packs of pen for $11, then ;

[tex]5x+2y=11 .... 2[/tex]

We will have to solve both equations simultaneously as shown;

[tex]2x+3y=8.25... 1...*5 \\5x+2y=11 ... 2 ... *2 \\[/tex]

---------------------------------------------------------------------------------------------------------------------------------------------------------

[tex]10x+15y=41.25\\10x=4y=22 \\[/tex]

Subtract the resulting equations;

[tex]15y-4y=41.25-22\\11y=19.25\\y=19.25/11\\y= $ 1.75 \\[/tex]

Hence 1 pack of pen costs %1.75

To get x, you will substitute y= 1.75 into equation 2;

[tex]2;5x+2y=11\\5x+2(1.75)=11\\5x+3.5=11\\5x=11-3.5\\5x=7.5\\x=\frac{7.5}{5} \\x=1.5[/tex]

Hence 1 pack of pencil will cost costs $1.5

From the above solution, we can conclude that there are enough information to find the cost of each pack of pen and pencil.

PLEASE MARK ME AS BRAINLIEST

Let the unit price for pencil be x

Let the unit price for pack be y

   

If the students bought 3 packs of pencil and 2 packs of pen for $8.25, then;

Similarly;

If her friend bought 5 packs of pencil and 2 packs of pen for $11, then ;

We will have to solve both equations simultaneously as shown;

---------------------------------------------------------------------------------------------------------------------------------------------------------

Subtract the resulting equations;

Hence 1 pack of pen costs %1.75

To get x, you will substitute y= 1.75 into equation 2;

Hence 1 pack of pencil will cost costs $1.5

From the above solution, we can conclude that there are enough information to find the cost of each pack of pen and pencil.