Question: Bill is laying power cable for a new neighborhood. There are going to be 18 east-west streets that are 2 miles long and 10 north-south streets that are four miles long. It takes 5 miles of cable to electrify 1 mile of street. If cable costs $2000/mile, what is the total cost of cable for the neighborhood? Think carefully first, then make a decision:
First find the total distance of the east - west streets: 18 streets * 2 miles / street = 36 miles. Then find the total distance of the north - south streets: 10 streets * 4 miles / street = 40 miles. Then add the number of miles from each type of street to find the total distance: 36 miles + 40 miles = 76 miles. Then multiply that number by 5 to find the number of miles of cable needed: 76 miles street * 5 miles cable / mile street = 380 miles of cable. Then multiply that number by the cost of one mile of cable to find the total cost: 380 miles * $2000 / mile = $760,000. So the answer is 760000.