Question

For his phone service, Charlie pays a monthly fee of $ 18 , and he pays an additional $ 0.06 per minute of use. The least he has been charged in a month is $
For his phone service, Charlie pays a monthly fee of $18, and he pays an additional $0.06 per minute of use. The least he has been charged in a month is $102.24
What are the possible numbers of minutes he has used his phone in a month?

Answer 1

Answer:

Charlie has used his phone in a month for at least 1404 minutes

Step-by-step explanation:

In order to solve this problem, we must first determine what will our variable be and what it will represent.

Let's say our variable is x and it will represent the number of minutes Charlie has used his phone.

After we set our variable up, we can set our equation up. The problem states that Charlie will pay a monthly fee of $18 and additional $0.06 per minute of use. The $18 is what is called a fixed cost and the $0.06 is the variable cost, which will depend on our variable x (the number of minutes spent). Taking this into account we can build an inequality that will represent the amount of money spent in a month, which will look like this:

$18+0.06x\geq 102.24$

so now we can solve that inequality for x, we can start by subtracting 18 from both sides, so we get.

$18+0.06x-18\geq 102.24-18\\\\0.06x\geq 84.24$

Next, we can divide both sides of the inequality by 0.06 so we get:

$0.06x/0.06\geq 84.24/0.06\\\\x\geq 1404$

so that's where the answer came from. Charly has used an amount of at least 1404 minutes