If we know that Akash's cell phone bill was $79.99 for a single month, we can understand what -239.97 is telling us. $79.99 is the cost per month for the cell phone bill. If we multiply 79.99 by 3, we now know that 239.97 represents how much the bill is at the end of the 3 months.
Therefore, Akash's cell phone bill at the end of the 3 months was 239.97.
The reason 239.97 has a negative sign in front of it is because Akash owes money.
