Question

Nick's telephone company charges $0.07 per minute for weekend calls and $0.08 per minute for calls made on weekdays. This month Nick was billed for 610 minutes. The charge for these minutes was. $48.05. How many minutes did he talk on weekends and how many minutes did he talk on​ weekdays?

Answer 1

 So pretend weekend calls is x and weekday calls are y.


the formulas is x + y = 610
                        0.07x + 0.08y = 48.05

So, x = 610 - y

Then, substitute x into the second equation.

0.07(610 - y) + 0.08y = 48.05
 42.7 - 0.07y + 0.08y = 48.05
                        0.01y = 5.35
                               y = 535


Then substitute y into the first equation.

x + 535 = 610
          x = 75

Just to be sure, substitute x and y into the second equation.

0.07(75) + 0.08(535) = 48.05
             5.25 + 42.80 = 48.05
                        48.05 = 48.05


So, on weekends, he used 75 minutes.
On weekdays, he used 535 minutes.