Suppose a poll of 819 adults asked how to deal with an energ

Suppose a poll of 819 adults asked how to deal with an energy shortage: use more production, more conservation, or both? Suppose 3 Response Number ch people are selected at random from this sample. What is the probability that all three responded \'More production\"? What is the probability that none responded \'Both\'? What assumption must be made to compute these probabilities? The events are independent. The events are disjoint. The events occur simultaneously. The order of the events does not matter.

Solution

a)

P( 3 selected are from More production) = 314 C 3 / 819 C 3 = nCr(314,3)/nCr(819,3) = 0.056

b)

P( None respond Both) = 1 - P( All respond Both) = 1 - nCr(85,3)/nCr(819,3) = 0.999

c)

events are independent