Question

Tanya is training a turtle for a turtle race. For every of an hour that the turtle is crawling, he can travel of a mile. At what unit rate is the turtle crawling?

Answer 1

1 mile per hour, or 1 mph

Answer 2

 For every ___ of an hour that the turtle is crawling, he can travel of a mile. At what unit rate is the turtle crawling?

What is supposed to be in the blank? I can't answer without that piece of info