Marco is draining his two aquariums. The tanks are the same size. One tank has 7 in. of water in it and is being drained at a rate of 1 in./min. The other tank has 5 in. of water in it and is being drained at a rate of 0.5 in./min. After how many minutes will the tanks contain the same amount of water?
Let x be the number of minutes it takes for the two tanks to contain the same amount of water, then 7 - x = 5 - 0.5x -0.5x + x = 7 - 5 0.5x = 2 x = 2/0.5 x = 4 mins
Therefore, the tanks will contain the same amount of water after 4 mins.
