Answer:
Step-by-step explanation:
I'm guessing you want to ask how long it will take to make it back. I will use hours.
400 dollars is how much they are in debt right now.
They are using 5 dollars an hour but also making 10 dollars an hour. That means they make a total of 5 dollars an hour.
400/5=80 hours for them to make the money back.
I wrote the steps down, hopefully you understand them and the answer is on the lower right corner.