Răspuns:
[tex]2\leq \frac{\frac{}{ab}}{5}\leq \frac{\frac{}{abc}}{50}[/tex]
Explicație pas cu pas:
a ≥ 1 ⇒ 2a ≥ 2
[tex]\frac{\frac{}{ab}}{5} =\frac{10a+b}{5} =2a+\frac{b}{5} \geq 2a[/tex]
[tex]\frac{\frac{}{abc}}{50} =\frac{100a+10b+c}{50} =2a+\frac{b}{5} +\frac{c}{50} \geq 2a+\frac{b}{5}[/tex]