First we have to find how much is the 120% of a dollar so we can made a rue of 3
[tex]\begin{gathered} 1\to100 \\ x\to120 \end{gathered}[/tex]and the equation will be:
[tex]x=\frac{1\cdot120}{100}=1.20[/tex]So to have 1.20 dollars we can have:
option 1: 1 coin of 1 dollar and two dimes
option 2: 1 coin of a dollar and 4 coins of 5 cents.
