2021 AMC 10A Problems/Problem 6
Contents
Problem
Chantal and Jean start hiking from a trailhead toward a fire tower. Jean is wearing a heavy backpack and walks slower. Chantal starts walking at miles per hour. Halfway to the tower, the trail becomes really steep, and Chantal slows down to
miles per hour. After reaching the tower, she immediately turns around and descends the steep part of the trail at
miles per hour. She meets Jean at the halfway point. What was Jean's average speed, in miles per hour, until they meet?
Solution 1 (Generalized Distance)
Let miles be the distance from the start to the fire tower. When Chantal meets Jean, she has traveled for
hours. Jean also has traveled for
hours, and he travels for
miles. So, his average speed is
miles per hour.
~MRENTHUSIASM
Solution 2 (Convenient Distance)
We use the same template as shown in Solution 1, except that we replace with a concrete number.
Let miles be the distance from the start to the fire tower. When Chantal meets Jean, she travels for
hours. Jean also has traveled for
hours, and he travels for
miles. So, his average speed is
miles per hour.
~MRENTHUSIASM
Video Solution (Using Speed, Time, Distance)
~ pi_is_3.14
See Also
2021 AMC 10A (Problems • Answer Key • Resources) | ||
Preceded by Problem 5 |
Followed by Problem 7 | |
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All AMC 10 Problems and Solutions |
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