Let’s run to class

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Two young mathematicians race to math class.

Check out this dialogue between two calculus students (based on a true story):

Devyn: Riley, I want to go to math class. Now. Look, this straight, long hall is empty. Let’s race!
Riley: Yes. Let’s race! On, your mark…. Ready. Steady. Go!
Devyn: You may think you’re fast, but I’m catching up!
Riley: Noooooo!
Devyn: Now I’m winning! I’ve never won a foot race in my life!
Riley: Never…give…up!
Devyn: Whew! We both made it to math class at exactly the same time!
Riley: Wow. We should run to every class. Hey I have a question, was there a time during our race that we were running at exactly the same speed?

Which of the following describes the race above?

Devyn was leading until the end, when the race finished in a tie. Riley was leading until the end, when the race finished in a tie. Devyn was leading, then Riley was leading until the end, when the race finished in a tie. Riley was leading, then Devyn was leading until the end, when the race finished in a tie. None of the above.

What can you say about Devyn’s and Riley’s average velocities?

Devyn has the larger average velocity. Riley has the larger average velocity. Their average velocities are equal. None of the above.

Since Devyn and Riley start and stop at the same time and place, their average velocities are equal.

Record your guess to Riley’s question: is there a moment during the race where Devyn and Riley were running at exactly the same speed?

Enter your guess of “yes” or “no”, then come back after the Dig-In to see if your guess was correct!