Anna buys 12 pens and 20 pencils for a total of $16. One pen costs $0.40 more than one pencil. What would 1 pen and 1 pencil cost?

Question

I do not get it

Answer 1

Let x = cost of 1 pencil

Let y = cost of 1 pen

 

   y = x + .40

12y + 20x = 16.00  Substitute (x + .40) for y

 

12(x + .40) + 20x = 16.00

 12x + 4.80 + 20x = 16.00

 

      32x = 16.00 - 4.80

      32x = 11.20

       32       32

       x = .35 cost of 1 pencil

 

    y = x + .40 = .75 = cost of 1 pen

 

A²

 

 

 

Answer 2

Let x be the cost of each pen

     x-0.40 be the cost of each pencil

 

12x + 20(x-0.40)  = $16  is the equation

 

Solve the equation:

 

12x + 20x - 8 = 16 

 

      32x = 24

 

          x =  0.75  is the cost of each pen

 

    x- 0.40 = 0.35 is the cost of each pencil