### If 1 gallon treats 1000 gallons how much do you need to treat 25 gallons?

This is a ratio: whatever : treat 1 gallon : 1000 gallon ? gallon : 25 gallon First find out how much treats 1 gallon (divide both sides by 1000): 1 ÷ 1000 gallon : 1000 ÷ 1000 gallon → 0.001 gallon : 1 gallon Now find out how much treats 25 gallons (multiply both sides by 25) 25 × 0.001 gallon : 25 × 1 gallon → 0.025 gallon : 25 gallon → you…