How much commission be if she sold 400$ worth of shirts

Given:-
Maria recives 2.5% commission when he sells $100 worth of t-shirts.
To find:-
What is the commission if he solds $400 worth of t-shirts.
Now to find the commission for $100. we get,
[tex]100\times\frac{2.5}{100}=2.5[/tex]So he gets $2.5 when he sold $100.
The commission for $400 is,
[tex]400\times\frac{2.5}{100}=4\times2.5=10[/tex]So he gets $10 when he sold $400.
So the required solution is $10.