Answer:
The bill size can be considered usual.
Step-by-step explanation:
Mean (μ) = $108.43
Standard deviation (σ) = $36.98
Now, consider the distribution to be normal distribution :
Now, finding values of z-score from the table. We get,
P(Z > 1.75) = 0.9599
⇒ 95.99%
So, only 4.01 % of the people in the city wastes water.
Hence, the bill size can be considered usual.