How can I persuade my Mom?

Question

ok so i want this game for the PC. I haven't asked my if i can get it yet though. I told my mom that i would pay for this thing i want and she said ok. But, if i tell her that its a computer game she might say that i can't buy it. She thinks i will waste my money or play it for the whole day without stopping. I already have one excuse. It is that school is starting soon and i won't be able to play it as much and i won't be able to play it the whole day because i will be at school. I need more reasons if that one does not work. Also, i need your opinions on my excuse. I need to know if it is good or not.

Answer 1

Mom:

I bet you will think this computer game is a waste of time, but it is something that I will enjoy.  Tell me the rules you are going to set for me playing it. How long? how late? I want to know before I spend the money.

That might work

Answer 2

its your money you buy what you want :)