things were not as complicated when I was in middle school.
6 foot makes 4.5 foot shadow
1 foot makes=4.5/6
so 50 foot =4.5/6*50 = tree makes 37.5 foot shadow
The next smaller tenth is 29.3 .
The next bigger tenth is 29.4 .
29.34 is nearer to 29.3 than to 29.4 .
So the nearest tenth is 29.3 .