The parasitic nematode Camallanus oxycephalus infects many freshwater fish, including shad. The following table gives the number of nematodes per fish (Shaw et al., 1998) Number of nematodes 0 1 2 Number of fish 103 72 44 14 3 1 1 4 45 5 6 Do nematodes infect fish at random? Pr[X] = X! Degrees of Probability of a larger value of x' Freedom 0.99 0.95 0.90 0.75 0.50 0.25 0.10 0.05 0.01 1 0.000 0.004 0.016 0.102 0.455 1.32 2.71 3.84 6.63 2 0.020 0.103 0.211 0.575 1.386 2.77 4.61 5.99 9.21 3 0.115 0.352 0.584 1.212 2.366 4.11 6.25 7.81 11.34 4 0.297 0.711 1.064 1.923 3.357 5.39 7.78 9.49 13.28 5 0.554 1.145 1.610 2.675 4.351 6.63 9.24 11.07 15.09 6 0.872 1.635 2.204 3.455 5.348 7.84 10.64 12.59 16.81 7 1.239 2.167 2.833 4.255 6.346 9.04 12.02 14.07 18.48 8 1.647 2.733 3.490 5.071 7.344 10.22 13.36 15.51 20.09 O 2.088 2.225 4.168 5900 9243 11 20 14.68 16.02 21.67