Multiply the first equation by 1.5, to get:
[tex](1.5)(24b + 4c) = 1.5(2.5)[/tex]
[tex]36b + 6c = 3.75[/tex]
Subtract the second equation from this:
[tex]6b = 1/2[/tex]
[tex]b = 1/12[/tex]
Substituting into the first equation:
[tex]24b + 4c = 2.5[/tex]
[tex]24*(1/12) + 4c = 2.5[/tex]
[tex]2 + 4c = 2.5[/tex]
[tex]4c = 0.5[/tex]
[tex]c = 1/8[/tex]
Therefore, it takes 1/12 minute to print a black-and-white page, and 1/8 minute to print a colored page.
