You use 4 gallons of water on 30 plants in your garden. At that rate, how much water will it take to

You use 4 gallons of water on 30 plants in your garden. At that rate, how much water will it take to water 45 plants?

Set up a proportion of gallons to plants:
4/30 = x/45 where x is the gallons of water needed for 45 plants.

Use our proportion calculator:
x = 6