Elementary school children spent significantly more time rea

\"Elementary school children spent significantly more time reading in the presence of a teacher than when the teacher was absent, t(7) = 2.804, p < 0.05 (2 = 0.46).\" In this related samples t test, how many participants were observed?

Solution

t(7) means df = 7, and participants must be 7+1 = 8

(unless the control group students were identical twins of those in experiment, making 8*2=16 participants in dependent samples)