Assume there is a 20% chance of an adult American suffering from a psychiatric disorder. Give answers accurate to four decimal places. (a) Find the probability that none of them them suffer from a psychiatric disorder.

b) Find the probability that exactly three of them suffer from a psychiatric disorder.

c) Find the probability that at least one of them suffers from a psychiatric disorder.

d) Find and interpret the mean of the random variable X where X is the number who suffer from a psychiatric disorder among for adult Americans.

Officer brimberry wrote 24 tickets for traffic violations last week, but only 9 tickets this week. what is the percent decrease? give your answer to the nearest tenth of a percent.

The price of a dozen eggs was $1.63. suppose the price increases m dollars per dozen and then the price decreases $0.12 per dozen. which expression represents the current price of eggs after the two price changes?

Ican interpret and represent the remainder in division calculations sensibly for the context (eg if we wont to know how many 40 seat buses will be needed to transport 170 students for on excursion, we divide 170 by 40 and realise buses and another smaller vehicle to that we need 4 transport 10 more students) solve the following questions. show your work! 11) the zoo had 420 butterflies that needed to be transported to a new enclosure. the boxes that the butterflies would be moved in only hold 80 butterflies in each. how many boxes would they need? 2 12) each classroom in the school can have exactly 25 students, if there are 345 students in the school how many full classrooms are there?