The house Trevor's family lives in has 6 people (including Trevor) and 3 bathrooms. In the past month, each person showered for an average of 480 minutes and used an average 72 liters of shower water (over the
entire month). Water costs 0.20 dollars per liter.
How much did Trevor's family pay per minute on shower water?

The amount Trevor's family paid per minute on shower water is $0.09

Step-by-step explanation:

The question parameters are;

The number of people in Trevor's family house = 6

The average total duration of each person's shower for the month = 480 minutes

The average volume of water used by each person for shower = 72 liters

The cost of the water per liter = 0.20 dollars/liter

The total cost of the shower water for the month = Total volume of water used for shower × Cost per liter of water

The total cost of the shower water for the month = 72 × 6 × 0.20 = $86.4

The total shower time duration for the 6 people = 480 × 6 = 2880 minutes

Given that there are three bathrooms, the time during the day spent showering = 2880/3 = 960 minutes

The amount paid per minute of shower water  = 86.4/960 = 0.09 dollars.

The amount Trevor's family paid per minute on shower water is 0.09 dollars.

step-by-step explanation: