Answer:
![\boxed {\tt 5 \ oranges}](https://img.qammunity.org/2021/formulas/mathematics/high-school/99t03zyiodir0jja8m9k6ee0gwzifo2q9u.png)
Explanation:
Let's set up a proportion.
![(oranges)/(minutes) =(oranges)/(minutes)](https://img.qammunity.org/2021/formulas/mathematics/high-school/8zx04de2kcg1e09nrer9m5fbeiemdygg3q.png)
He can peel 125 oranges in 5 hours. First, let's find the minutes in 5 hours.
There are 60 minutes in 1 hour, so multiply 60 and 5 (60*5=300). There are 300 minutes in 5 hours.
![(125 \ oranges)/(300 \ minutes)=(oranges)/(minutes)](https://img.qammunity.org/2021/formulas/mathematics/high-school/tcwutr5ggiigf110uvc62g95w3tbs4mu5t.png)
We don't know how many oranges he can peel in 12 minutes. So we say he can peel x oranges in 12 minutes.
![(125 \ oranges)/(300 \ minutes)=(x \ oranges)/(12 \ minutes)](https://img.qammunity.org/2021/formulas/mathematics/high-school/l3qikz2u54g6exiqq8phpc7aelb2vx7bu2.png)
![(125 \ )/(300 \ )=(x \ )/(12 )](https://img.qammunity.org/2021/formulas/mathematics/high-school/r7ghidexbqyau8e1pd8v49yycxesdkor0f.png)
Solve for x by isolating it. x is being divided by 12. The inverse of division is multiplication. Multiply both sides of the proportion by 12.
![12*(125 \ )/(300 \ )=(x \ )/(12 \ )*12](https://img.qammunity.org/2021/formulas/mathematics/high-school/g0p1g69takzt0b1z83wd02jqef2dg9bpfb.png)
![12*(125 \ )/(300 \ )=x](https://img.qammunity.org/2021/formulas/mathematics/high-school/wa7cpup238pscxe2hqw1rsr3nm2aucabzb.png)
![12*0.416666667=x](https://img.qammunity.org/2021/formulas/mathematics/high-school/flhh7bazi30pil7zhc7oz4kamtih7oaqyg.png)
![5=x](https://img.qammunity.org/2021/formulas/mathematics/high-school/uzj6sjhhakbk6pjb2daalvgmz0jtksrdc2.png)
Rob can peel 5 oranges in 12 minutes.