Answer:
Step-by-step explanation:
Alright, lets get started.
Suppose number of cars to be washed is x
You are charging $10 per car, so profit of yours after subtracting the supplies = [tex]10x -25[/tex]
Your friend is charging $ 13 per car, so his profit after subtracting the supplies = [tex]13x-55[/tex]
Both the amount earned are same, so
[tex]10x-25=13x-55[/tex]
[tex]3x=30[/tex]
[tex]x=10[/tex]
hence, you are washing 10 cars. : Answer
Hope it will help :)