5 bad oranges are accidently mixed with 20 good ones.if four oranges are drawn one by one successively with replacement ,then find the probability distribution of number of bad oranges drwan.hence find the mean and variance of the distribution
take the probability n=4 ,p=4/5 and q=1/5
now the distribution table would be like
0 1 2 3 4 4C0(4/5)0(1/5)44C1(4/5)1(1/5)3 4C2(4/5)2(1/5)2 4C3(4/5)3(1/5)1 4C4(4/5)4(1/5)0
Mean = np=16/5 Variance=npq=16/25