For this problem we know that David worked 7 173 hours today and planted 11 trees. And we want to find How long did it take him to plant each tree?
So we can set up the following equation:
![(11\cdot3)/(22)=(x)/(1)](https://img.qammunity.org/2023/formulas/mathematics/high-school/8172s1pc1jvn8pzuw7n7hwvley7q89sohu.png)
And solving for x we got:
![x=1.5\text{ hr}](https://img.qammunity.org/2023/formulas/mathematics/high-school/twfmbjlys2by4ejxyr52a528kdne1ugqpc.png)
It took him 1.5 hour to plant each tree.