Twenty (20) pigs of similar age and weight were selected for an experiment to compare the effects of two different rations on weight gain (in kg). The pigs were paired, with each pair being littermates. One pig in each pair was chosen at random and given Ration I and the other given Ration II.

Pair 1 2 3 4 5 6 7 2 9 10 Ration I 58 39 45 45 37 58 43 42 66 44 Ration II 34 44 41 40 44 31 36 44 44 50