If researchers wish to compare four brands of toothpaste on the basis of taste and freshness, how many comparisons are required in a paired comparison measurement?
A) Four
B) Six
C) Eight
D) 10

Question

Quizplus · Accepted Answer

To compare four items (brands of toothpaste) with each other in pairs, the formula n(n-1)/2 is used, where n is the number of items. Substituting 4 for n gives 4(4-1)/2 = 6 comparisons.

If Researchers Wish to Compare Four Brands of Toothpaste on the Basis