3 1/2 = 3.5
Each 10 minutes, the water faucet leaks 3.5 liters of water. And 1 hour is constituted of 60 minutes. Let x be the liters of water leaked in 1 hour, and let's use the rule of three:
10 minutes --> 3.5 liters
60 minutes --> x
x = (60*3.5)/10 = 21
So in 1 hour, the water faucet leaks 21 liters of water.
Hope this Helps! :)
