3. In Kansas, Highway A runs due north-south for 125 miles and Highway B runs dues east-west for 222 miles. The elevation of both highways is constantly 725 feet their entire lengths. The highways intersect at a point exactly halfway through their runs. One Tuesday a car is travelling east on Highway B at the constant speed of 76 mph and a truck is traveling north on Highway A at a constant speed of 84 mph. The car passes through the point of intersection at 4:12 pm and the truck passes through the point of intersection at 4:17 pm. At what rate is the distance between the two vehicles changing at 4:27 that afternoon? Assume that the speeds of the car and truck do not vary at all between 4:10 pm and 4:30 pm.
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Step 1: Calculate the distance traveled by the car in 15 minutes: Distance = Speed x Time Distance = 76 mph x (1/4) hour Distance = 19 miles Show more…
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