### Home > CALC > Chapter 7 > Lesson 7.4.1 > Problem7-174

7-174.

Newton High is located at the intersection of a north-south road and an east-west road. The calculus students are looking out the class window in disbelief at two students, Shant and Narek, who are rounding the corner on pogo sticks! The students see Shant traveling toward the school from the east. Narek is traveling north away from the school. Shant is travelling at $10$ ft/min at the moment he is $30$ ft from the school. At the same time, Narek is $40$ ft from the school going at $8$ ft/min. Determine whether the distance between the two students is increasing or decreasing. .

Implicitly differentiate with respect to time. Then evaluate the given values.

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