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Groups of people aged 15鈥�65 are randomly selected and arranged in groups of six. The random variable xis the number in the group who say that their family and / or partner contribute most to their happiness (based on a Coca-Cola survey). The accompanying table lists

the values of xalong with their corresponding probabilities. Does the table describe a probability distribution? If so, find the mean and standard deviation.

In Exercises 7鈥�14, determine whether a probability

distribution is given. If a probability distribution is given, find its mean and standarddeviation. If a probability distribution is not given, identify the requirements that are not satisfied.

When conducting research on color blindness in males, a researcher forms random groups with fivemales in each group. The random variable xis the number of males in the group who have a form of color blindness (based on data from the National Institutes of Health).

In Exercises 6鈥�10, use the following: Five American Airlines flights are randomly selected, and the table in the margin lists the probabilities for the number that arrive on time (based on data from the Department of Transportation). Assume that five flights are randomly selected.

What does the probability of 0+ indicate? Does it indicate that among five randomly selectedflights, it is impossible for none of them to arrive on time?

In Exercises 7鈥�14, determine whether a probability

distribution is given. If a probability distribution is given, find its mean and standarddeviation. If a probability distribution is not given, identify the requirements that are notsatisfied.

Ted is not particularly creative. He uses the pickupline 鈥淚f I could rearrange the alphabet, I鈥檇 put U and I together.鈥漈he random variable xis the number of women Ted approachesbefore encountering one who reacts positively.

Identifying Binomial Distributions. In Exercises 5鈥�12, determine whether the given procedure results in a binomial distribution (or a distribution that can be treated as binomial). For those that are not binomial, identify at least one requirement that is not satisfied.

Surveying Senators The Senate members of the 113th Congress include 80 males and 20 females. Forty different senators are randomly selected without replacement, and the gender of each selected senator is recorded.