A company needs to make 40.6 km of cable for customer. The machine making the cable can create 4.7 km of cable per hour. Where the company is working on the cable the customer add 6 km to the order please give me an equation on how I would solve this problem

A pipe is filling a storage tank with water at the rate of 17.5 gallons per minute partway through the process of a worker drains out 375 gallons which question could be used to find how many minutes it will take for the tank to reach its capacity of 5000 gallons. Is it 5000 X -17.5 equals 375?