A salt water solution is made by dissolving two pounds of salt in nine gallons of water. At this rate, how many pounds of salt is needed for 18 gallons of water?

4 pounds will require 18 gallons of water at the same rate.

Step-by-step explanation:

According to the question, to make a salt water solution one dissolved two pounds of salt in nine gallons of water. At this same rate he/she wants to dissolve a particular pounds of salts to 18 gallons to get the same salt water solution. Mathematically,

if 2 pounds requires 9 gallons

y pounds requires 18 gallons

that is 2 pounds = 9 gallons

y pounds = 18 gallons

cross multiply

9y = 18 * 2

9y = 36

y = 36/9

y = 4

Therefore,

4 pounds will require 18 gallons at the same rate.

You would need 4 pounds of salt for 18 gallons of water.