Suppose that in a large metropolitan area, 85% of all households have cable tv. Suppose you are interested in selecting a group of six households from this area. Let X be the number of households in a group of six households from this area that have cable tv. For what proportion of groups will exactly four of the six households have cable tv?

Solution :

Let X denotes the number of the households tha have a cable TV.

Percentage of household that have a cable TV = 85 %

Here, we can see that each of the observations is independent and the number of the observations is fixed, n.

The probability of the success P is the same for each of the outcomes.

Therefore,

               = 0.08324

maximum area = xy = (16)(32) = 512 ft2

to maximize the area of the garden, the side of the fence parallel to the side of the house should be 32 ft long, and the other two sides should both have length 16 ft.'

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