Pang dagdag points niyo sagutan niyo nalang ng tamang sagot, yung tamang sagot i ha high rate ko 15 + 89 - 53 + 8 - 3 =___ ÷ 2 =_?

How do i do this? i don’t understand

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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