The answer is 6 gallons
Step by step explanation
rap POS use 4 gallons of water on 30 plants
Using this expression
Plants = rate x gallons of water used
rate = plants / gallons of water used
rate = 30 / 4
rate = 15\2
We can get the amount of gallons used for 45 plants using the same expression
since our new rate is 15/2
then, plants = rate x gallons of water used
new plants is 45 and rate is 15/2
gallons of water used = Plants / rate
gallons of water used = 45 divided by 15/2
gallons of water used = 45 x 2/15
gallons of water used = 90/15
gallons of water used is 6 gallons