Question

Your cellphone plan gives you 500 minutes monthly. If you have used 310 minutes already and there is a week left this month, how should you use your minutes this last week? How many minutes could you use each day if you split the remaining minutes amongst the days?

Answer 1

Minutes left is 500 - 310 = 190 minutes

There are 7 days in a week

We can divide the minutes left by the days left = 190 ÷ 7 = 27.14 minutes per day rounded to 27 minutes

OR

We can check if there are days during the week we'd need to use the minutes more than the other days. 

Answer 2

In this case, you already used 310 minutes out of 500 minutes monthly. So the remaining time for your cell phone should be: 500 minutes -310 minutes= 190 minutes.
You still have 1 week this month, that means the 190 mins time must be divided into 1 week or 7 days. Then the duration you of cell phone use for each day should be: 190 minute/7days= 27.14 minutes/day