Do these angles make a linear pair?

Apositive number a or the same number a increased by 50% and then decreased by 50% of the result?

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?

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