Question

Assuming that one-third of the population is te drinkers and each of 1000 enumerators
takes a sample of 8 individuals to find out whether they are tea drinkers or not, how many
enumerators are expected to report that five or more people are tea drinkers?
(a) 100
(b) 95
(c) 88
(d)90​

Answer 1

Answer:

c - 88

....................

Answer 2

assume that being a tea drinker is like taking a flip of coin.(i.e. either the person drinks tea or not) with the probability of heads being 1/3 and tails being 2/3 now P(X>=5) =P(X=5)+P(X=6)+P(X=7)+P(X=8) = (56*8+28*4+8*2+1)/6561 = 577/6561 =0.087943 so for 1000 trials the number of trials which report greater than or equal to 5 is 1000*P(X>=5) = 87.94 =88

Therefore, the option c is correct ans