A cable is to be run from a power plant on one side of a river 900 meters wide to a factory on the other side,6,000 meters downstream.The cost of running cable under the water is $5 per meter,while over land is $4 per meter.What is the most economical route over which to run the cable?
A)The cable reaches the opposite bank 6,000 meters downstream.
B)The cable reaches the opposite bank 3,000 meters downstream.
C)The cable reaches the opposite bank 1,200 meters downstream.
D)The cable reaches the opposite bank directly across stream.

Question

Quizplus · Accepted Answer

The most economical route involves minimizing the total cost, which is a combination of the underwater and overland costs. By using calculus or optimization techniques, it can be determined that reaching the opposite bank 1,200 meters downstream minimizes the total cost.

A Cable Is to Be Run from a Power Plant