Question

Both questions please.

To protect a large investment of electronics found in a room, 4 ar conditioning units are used to cool the room. The probability that any air conditioning unit operates correct is 0.785. Asume the air conditioning unit operates Independently. Find the probability that one conditioning interes correctly Provide a 4 cm s tead the mean show QUESTION 19 A grocery store is nosted in determining whether or not a dece swits between the shore of Hot Now doughnuts dugu Yam doughnut Arndom of 100 booteach and days was determined for each brand. A BOX confidence interval for the difference of them was determined to be 1,24 Interpret the given confidence trval Since the values in the confidence interval are positive the proboy that the mean of Window s longer than the means of New doughnuts Based on this sample we are confident that Yum doughnuts willston vergeben 1.1 and 24 de ore than Horn Now doughnuts There is a chance that a randomly selected box of Horn Now doughnuts will have a shell is between 1 and 2.4 days to get don e d box of Sugar Yum doughnuts. Since the values in the confidence intervare positive, the probability that the mean shell of Hon Now dough is longer than the mean shelf life of Suge Yum doughnuts is 90% Based on this sample, we w BON confident that Horn Now doughnuts will last on average between 1.1 and 2.4 daylonger than Sugar Yum doughnuts.

Answer 1

First question:

Let X is a random variable shows the number of units operates correctly. Here X has binomial distribution with following parameters

n=4 and p=0.785

The probability that at least one unit operates correctly is

P(X > 1) = 1 - P(X = 0) = 1 - (1) (0.785)°(1 – 0.785)4-0 = 0.9979

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19:

Last option is correct.