Question

Jenny wants to determine if a new brand name washing detergent is better than her old detergent. She washes 10 dirty T-shirts with the new washing detergent. After washing, she thinks they are cleaner using the new detergent. What can she do to be sure the new washing detergent works better than the old detergent?

Answer 1

Jenny can:

1). Define what she means by "better".

2). Take 20 T-shirts, all sullied by a wide variety of types of dirt, soil, schmutz, grime, dust, soot, mud, filth, mire, sludge, slime, ooze, dross, waste, stains, crud, grunge, and yuck.

3). Close her eyes, and, by feel alone, select 10 T-shirts out of the 20.

4). Wash 10 shirts with her old detergent. Wash 10 other shirts with her new detergent. After washing, keep the two groups of shirts segregated in separate piles.

5). Invite 5 of her closest friends to her house for soda and chips.

After snacks, tell them she needs their opinions. Don't tell them anything about the detergents.

Put the two piles of T-shirts on a large table.

Tell them what "better" or "cleaner" means to her.

Let each friend feel, palpate, inspect, evaluate and examine the two piles, and the T-shirts in each pile, being careful not to mix the piles.

6). Finally, ask each friend which pile of shirts s/he thinks more closely meets Jenny's definition of "cleaner" or "better".