Answer:
8.4
Step-by-step explanation:
1 orange → [tex]x[/tex]
1 apple → [tex]y[/tex]
[tex]\frac{\begin{matrix}\space\space&5n&+&7y&=\textbf{6.90}\\ +&5n&+&20y&=\textbf{16.00}\end{matrix}}{\begin{matrix}\space\space&\space\space&\space\space&\space\space&\textbf{+13y = +9.1}\end{matrix}}\\y = 0.7[/tex]
↓
[tex]3n + 12y = 9.6\\3 (n+4y) = 3 (3\cdot2)\\x + 4y = 3.2\\5 (n+4y) =5 (3\cdot2)\\5x + 20y = 16[/tex]
12 apples → [tex]12 \times 0.7[/tex]
→→→→→ 8.4
