In an experiment conducted at a laboratory, 160 white mice were injected with Serum D. 160 other white mice were injected with a harmless sugar solution. In two weeks time 39% of the white mice, who were injected with Serum D contracted the highly contagious and often fatal disease, jungle fever. Hence, it can be concluded that jungle fever is caused by some elements similar to the elements in Serum D.
The above discussion would be weakened most severely in case it is shown that
A jar has 5 marbles, 1 of each of the colours red, white, blue, green, and yellow. If 4 marbles are removed form the jar, what is the probability that the yellow one was removed ?
