Ans: B
Let $\$x$ and $\$y$ be the prices of an orange and apple respectively.
Let $\$x$ and $\$y$ be the prices of an orange and apple respectively.
$\left\{ \begin{array}{ll}
6x + 3y = 42 & \ldots \unicode{x2460} \\
8x + 5y = 60 & \ldots \unicode{x2461}
\end{array} \right.$
From $\unicode{x2460}$, we have
$\begin{array}{rcl}
6x + 3y & = & 42 \\
2x + y & = & 14 \ \ldots \unicode{x2462}
\end{array}$
$\unicode{x2461} – 4 \times \unicode{x2462}$, we have
$\begin{array}{rcl}
8x + 5y -4(2x+y) & = & 60 – 4(14) \\
8x +5y -8x – 4y & = & 4 \\
y & = & 4
\end{array}$
Therefore, the price of an apple is $\$4$.
