how to convine my mother to let me have a rc car petrol?

Answer 1

Instead of trying to convine your mom how about
earning it instead. Make a deal with your mom
that if you earn half of the money would she put
up the rest. That way you will show her that you
are responsible and will take care of it. Of course
getting mom's permission should be first.

Answer 2

Let your mother have her way. When you're out of the house, you can buy whatever you want, but for now she has a right to run things HER way. This is her life too, and maybe she doesn't have time to take you to the E.R. with gasoline burns, or have to come home from work and breathe fumes from spilled gas.
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