The total distance covered from Monday to Wednesday is 12 + 18 + 21 = <<12+18+21=51>>51 miles.

So the average distance traveled per day is 51/3 = <<51/3=17>>17 miles.

# Answer

17
Question:
If a vehicle is driven 12 miles on Monday, 18 miles on Tuesday, and 21 miles on Wednesday. What is the average distance traveled per day?
Answer:
Let's think step by step.

user
17
If a vehicle is driven 12 miles on Monday, 18 miles on Tuesday, and 21 miles on Wednesday. What is the average distance traveled per day?
train