Using proportions, it is found that it will take 4 hours for Phoebe to catch Candice.
A proportion is a fraction of a total amount, and the measures are related using a rule of three.
Given their velocities, and the fact that they travel in the same direction, each hour, Phoebe gets 10 mph closer to Candice.
The initial distance is of 40 miles, 40/10 = 4, hence it will take 4 hours for Phoebe to catch Candice.
More can be learned about proportions at https://brainly.com/question/24372153
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