Answer:
Option D
Step-by-step explanation:
Combine Like Terms.

Hope this helps.
What we know:
Lot= 21 x 30ft
Perimeter=2l+2w
Want to put 4 corner post and one post every 3 ft
What we need to find:
How many post we need.
Perimeter=2 (21)+2 (30)=42+60=102ft
102/3=34
34 posts are needed.
Multiply 2/3 by 8 and you will get 16/3 or 5.33 repeating.
Your answer would be B.
HOPE THIS HELPS YOU! ^_^