Final answer:
Joe can save $156 by bringing water from home instead of buying Gatorade for his son.
Step-by-step explanation:
To calculate the amount of money Joe can save by bringing water from home instead of buying Gatorade, we need to determine the total number of Gatorades he would buy in half a year, and then calculate the cost of those Gatorades. Joe's son plays hockey 3 times a week for half a year, which is 26 weeks. So the total number of Gatorades Joe would buy is 3 Gatorades/week x 26 weeks = 78 Gatorades.
Now, to determine the cost of those 78 Gatorades, we multiply the number of Gatorades by the cost of each Gatorade, which is $2. So the total cost of those 78 Gatorades would be $156.
Therefore, Joe can save $156 by bringing water from home instead of buying Gatorade for his son.