Testing paper towel strength will help you determine which brand provides the best deal. Though one brand of paper towels may be less expensive than another, its lack of durability may make it less cost-efficient. Many paper towel brands advertise their product's superior strength. Brawny labels its paper towels with the tagline "Premium Performance" and Bounty promises "One Sheet Keeps Cleaning." It is possible to find out for yourself which brand stands up to its label.
Hang one sheet of paper towel across the seat of two flat-surfaced kitchen chairs so that each chair has an equal amount of paper towel with a portion of the towel suspended between the chairs. Place two equally-weighted hardback books on each side of the paper towel to secure it.
Another option is to have two friends each hold onto one side of the sheet by its corners. Instruct your friends to pull the paper towel so it is slightly taut but not so it is strained or ripping.
Release 10 water droplets from the liquid dropper onto the middle of the paper towel sheet. A standard medicine eyedropper works well. This allows you to test the paper towel's strength of when wet. Since paper towels usually get wet while cleaning, it is more useful to test wet paper towel strength rather than dry paper towel strength.
Place marbles one at a time on the wet area in the middle of the paper towel. Count how many marbles the paper towel holds until it breaks. Record the number of marbles each brand holds before testing another brand.
Repeat the process using different brands of paper towels. If you are able to place all your marbles onto the paper towels without any sheets breaking, increase the number of water droplets you release onto the paper towel to 20. Keep the number of water droplets used constant for each brand of paper towel.
Compare each brand of paper towels to see which can hold the most marbles. The strongest paper towel brand is the one that held the highest number of marbles without breaking. The weakest paper towel brand is the one that broke from the fewest number of marbles.
Compare the different brands' "marble scores" with their costs to determine which is the most cost-efficient brand. Do this by dividing the price of each brand of paper towel by the number of marbles it held. The paper towel with the lowest dollar per marble score has the best strength value for your money.