Least common multiple of 21, 33, 57

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?

Need asap. solve for the following inequality

Determine domain and range, largest open interval, and intervals which function is continuous.