Let 'x' be the amount of nickels Anna has, and 'y' the amount of dimes.
If she has '4 more nickels than dimes' this is:
[tex]y=x+4[/tex]And the total amount is $1.25, that can be written as:
[tex]0.05\cdot x+0.10\cdot y=1.25[/tex]If we replace the equivalence between y and x here we get:
[tex]0.05x+0.10(x+4)=1.25[/tex]The correct answer is option C