Question that needs to be solved: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?=> 4 gallons is to 30 plants.=> 4 gallons / 30 plants = 0.13 gallons per plants.Now, it needs to water around 45 plants, let us solve how much will it need => 0.13 gallons * 45 plants = 6 gallonsThus, to water 45 plants you need to have 6 gallons of water