We have the following:
we can solve the question by means of the following system of equations
let x, nickel ($0.05)
let y, dime ($0.10)
[tex]\begin{gathered} x+y=15\rightarrow y=15-x \\ 0.05x+0.10y=1.20 \end{gathered}[/tex]solving:
[tex]\begin{gathered} 0.05x+0.10\cdot(15-x)=1.20 \\ 0.05x+1.50-0.1x=1.20 \\ 0.1x-0.05x=1.50-1.20 \\ 0.05x=0.30 \\ x=\frac{0.30}{0.05} \\ x=6 \end{gathered}[/tex]The answer is B. 6 nickels
