Final answer:
To find out how long Peter's water will last, divide the total amount of water he has (8 gallons) by the amount he drinks per day (1/5 gallon), giving a result of 40 days.
Step-by-step explanation:
To find out how long Peter's water will last, we can divide the total amount of water he has (8 gallons) by the amount he drinks per day, which is 1/5 gallon.
To divide fractions, we can multiply the first fraction (8 gallons) by the reciprocal of the second fraction (5/1).
This gives us: 8 gallons ÷ (1/5) gallon = 8 gallons × (5/1) = 8 × 5 = 40 days.
So, Peter's 8 gallons of water will last him 40 days.