In your own words, what is a interquartile range?
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Monthly water bills for a city have a mean of $108.43 and a standard deviation of $32.09. find the probability that a randomly selected bill will have an amount greater than $155, which the city believes might indicate that someone is wasting water. would a bill that size be considered unusual?

Just tell me how to set up the equation.

Which equation represents a direct linear variationa. y=x2b. y=2/5xc. y=1/xd. y=x+3