Question

A pool technician recorded the water loss in the pool from a drain leak over time. Hours (x) 2 4 6 8 Water loss (gal) (y) 4 8 12 16 The water loss is proportional to the time. How long will it take the pool to lose 120 gallons of water?

Answer 1

60 hours to lose 120 gallons of water.

Explanation:

Make a spreadsheet of the data with 3 columns. The first will contain the hours and the second will contain the gallons of water lost. (attached). It would be useful to have a water loss rate, such as gallons lost per hour. So in the third column, take the gallons of water for that line and divide it by the hours for that same line. Do this for each of the line entries, as shown. The first thing to note is that they are all the same. Perfect! (and important). This means we can use the rate of 2 gallons per hour and multiply it by the number of hours to find the total water lost:

(Rate[gal/hr])x(Time[hr]) = Gallons water lost

The question is how mush time until 120 gallons are lost. The unknown is the hours, which we'll call x. Now we can set up the equation and solve for x:

(Rate[gal/hr])*(Time[hr]) = Gallons water lost

(2 gal/hr)*(x) = 120 gallons water

x = 60 hours to lose 120 gallons of water.