Math(module 4 Calculus)
(minimum commuting time) A lighthouse lies 2 miles offshore directly across from point A of a straight coastline. The lighthouse keeper lives 5 miles down the coast from point A.What is the minimum time it will take the lighthouse keeper to commute to work, rowing his boat at 3 miles per hour, and walking at 5 miles per hour?
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The lighthouse keeper will have to travel a total distance of 7 miles, meaning it will take him a minimum of 2.4 hours to commute to work. This is because rowing the boat for 2 miles at 3 miles per hour will take 40 minutes (2 miles/3 mph = 40 minutes), and walking 5 miles at 5 miles per hour will take 1 hour (5 miles/5 mph = 1 hour). Adding the two together yields a total of 2.4 hours (40 minutes + 1 hour = 2.4 hours).
