A weapons manufacturer uses a liquid propellant that can get
mixed with another liquid to produce a contaminated cartridge. A
statistician found that 24% of the cartridges in the particular
lot were contaminated. Suppose you randomly sample (without
replacement) gun cartridges from this lot until you find a
contaminated one. Let x be the number of cartridges sampled until a
contaminated one is found. It is known that the probability
distribution for x is given by the formula shown below....