Question

If 10 pencils and 7 erasers cost $4.23 and 3 pencils and 1 eraser cost $0.95, what is the cost of 2 erasers?

Answer 1

Answer: $0.58

Step-by-step explanation:

Let x represent pencil and y represent eraser

10x + 7y = 4.23   →   1(10x + 7y = 4.23)   →   10x + 7y =  4.23

3x  + y  = 0.95   →  -3(3x  + y  = 0.95)   →   -21x - 7y = -6.65

                                                                    -11x         = -2.42

                                                                  ÷-11             ÷-11      

                                                                         x        = 0.22  

      3x + y = 0.95

3(0.22) + y = 0.95

   0.66 + y = 0.95

               y = 0.29

2y = 2(0.29)  = 0.58