In a study of the development of the thymus gland, researchers weighed the glands of 10 chick embryos. Five of the embryos had been incubated 14 days, and five had been incubated 15 days. The thymus weights were as shown in the table.

(a) Use a t test to compare the means at α = 0.10.
(b) Note that the chicks that were incubated longer had a smaller mean thymus weight. Is this "backward" result surprising, or could it easily be attributed to chance? Explain.

Transcribed Image Text:

Thymus weight (MG) 14 Days 29.6 21.5 28.0 34.6 44.9 15 Days 32.7 40.3 23.7 25.2 24.2 /t 31.72 8.73 29.22 719