Company charges .03 per minute on weekends and .07 on weekdays.

Question

Billed $542 minutes this month. Charged $29.06 for minutes. How many minutes did he talk weekdays and weekends?

Answer 1

Hello, thank you for taking the time to post your question!

The key on this type of question is to set up an expression that models that information given. For this one we can form 2 equations

W + E = 542    since the total minutes talked is 542 (“W” is weekdays and “E” is ends)

0.07W + 0.03E = 29.06  based on the cost

Then you can plug in W = 542 – E into the second expression and solve algebraically

0.07(542 – E) + 0.03E = 29.06

37.94 – 0.07E + 0.03E = 29.06

-0.04E = -8.88

E = 222

W = 542 – 222 = 320

So the person talked for 320 minutes on weekdays and 222 minutes on weekends

I hope that helps get you moving in the right direction! Feel free to reach out if you have any additional questions beyond that :)

Answer 2

Roger, let e = weekend minutes and d = weekday minutes.

 

d + e = 542, right?

 

.07d + .03e = 29.06. We can multiply both sides by 100.

 

7d + 3e = 2906

 

Now, we  "solve" the first equation for d or e. Let's do e.

 

e = 542 - d

 

Use this "value" for e in the second equation.

 

7d + 3(542 - d) = 2906

 

Solve for d and plug that value into the first equation to find e.

 

Hope this helps!