---
title: "Mary and Sally are in a foot race. When Mary is \\( 22 \\) \\( \\text{m} \\) from the finish line, she has a speed of \\( 4.0 \\) \\( \\text{m/s} \\) and is \\( 5.0 \\) \\( \\text{m} \\) behind Sally, who has a speed of \\( 5.0 \\) \\( \\text{m/s} \\). Sally thinks she has an easy win and, during the remaining portion of the race, decelerates at a constant rate of \\( 0.40 \\) \\( \\text{m/s}^2 \\) until she reaches the finish line. What constant acceleration must Mary maintain during the remaining portion of the race if she wishes to cross the finish line side-by-side with Sally?"
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url: "https://nerd-notes.com/ubq/98414/"
date_modified: "2025-07-26T03:06:43+00:00"
---

# Mary and Sally are in a foot race. When Mary is \( 22 \) \( \text{m} \) from the finish line, she has a speed of \( 4.0 \) \( \text{m/s} \) and is \( 5.0 \) \( \text{m} \) behind Sally, who has a speed of \( 5.0 \) \( \text{m/s} \). Sally thinks she has an easy win and, during the remaining portion of the race, decelerates at a constant rate of \( 0.40 \) \( \text{m/s}^2 \) until she reaches the finish line. What constant acceleration must Mary maintain during the remaining portion of the race if she wishes to cross the finish line side-by-side with Sally?

Mary and Sally are in a foot race. When Mary is \( 22 \) \( \text{m} \) from the finish line, she has a speed of \( 4.0 \) \( \text{m/s} \) and is \( 5.0 \) \( \text{m} \) behind Sally, who has a speed of \( 5.0 \) \( \text{m/s} \). Sally thinks she has an easy win and, during the remaining portion of the race, decelerates at a constant rate of \( 0.40 \) \( \text{m/s}^2 \) until she reaches the finish line. What constant acceleration must Mary maintain during the remaining portion of the race if she wishes to cross the finish line side-by-side with Sally?

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/98414/*