In a randomized comparative experiment on the effect of color on the performance of a cognitive task, researchers randomly divided 66 subjects (24 males and 42 females ranging in age from 17 to 25 years) into three groups. Participants were asked to solve a series of 6 anagrams. One group was presented with the anagrams on a blue screen; one group saw them on a red screen; and one group had a neutral screen. The time, in seconds, taken to solve the anagrams was recorded. The paper reporting the study gives x¯¯¯= 11.49 and s=4.39 for the times of the n= 20 members of the neutral group.