Someone me ❗️ okay so i know how to solve the problem but at the end you must either subtract or add and i thought if the graph line was going down (like in the picture) i would subtract.. but for this problem i had to add and now i’m very confused.. if someone could explain why i had to add instead of subtract that would be great.

did you read it? it said how much is left after 33 minutes of calling so subtract it from 42 then convert it into percentage then decimal there you gote your answer.(I think it was a little confusing to me then again i am in 7th grade)

You would add since the graph is giving you 42 minutes of calls, and you would only want 33 minutes of phone calls. I would add 9 minutes of credit to the 42 and get the correct answer.

I don't know if I'm making any sense, but just comment down below if you get it or not!