For his phone service, Michael pays a monthly fee of $13,and he pays an additional.$0.06 per minute of use. The least he has been charged in a month is $85.30.

Question

What are the possible numbers of minutes he has used his phone in a month?
Use m for the number of minutes,and solve your inequality for m

Answer 1

Let's assume that in a month Michael has used his phone for m minutes.

The additional cost for the minutes of use is given by 0.06m.
Therefore, the total cost for the month is 13 + 0.06m.

According to the given information, the least he has been charged in a month is $85.30.
So we can set up the following inequality:

13 + 0.06m ≥ 85.30

We can solve this inequality for m.

13 + 0.06m ≥ 85.30
Subtract 13 from both sides:
0.06m ≥ 72.30
Divide both sides by 0.06 (which is the coefficient of m):
m ≥ 1205

So the possible numbers of minutes he has used his phone in a month are m ≥ 1205.