You have 5 gallons of water and you want to add soap to the mix, the total to add up to 100%.

So 5 gallons = 97% of the mix, so, 5 /97 = 0.051546 gallons or 1 %, therefore 3% is 0.1546 gallons.

There are eight pints in a gallon , so, 8 x 0.1546 = 1.237 pints, or, 703 millilitres!

The total Volume you will have is 5.155 gallons. So if you have 5 gallons of water you would need to add about 2/3 of a quart of soap or 20 ounces of Soap. Now if your pail is 5 gallons at about 19 ounces of soap then fill it up to the five gallon level.

...I gave you the wrong amount in my first answer. The correct amount should be: If you have 5 gallons of water that is equal to 41.65lbs. and 3% of that is 1.25lbs. So you would need to add 1 1/4 lbs. of soap. Sorry for the original mistake.

...The answer is 567.8ml or about 2.4cups

So if it was me I would fill the bucket with water take out 2.5 cups of water and then add 2.5 cups of soap. Good luck

If you have 5 gallons of water the total weight of that water is 37.4 lbs. So if you need 3% then you would need to add .03 x 37.4 = 1.1 lbs of soap.

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