Question

The amount of rainfall in january in a certain city is normally distributed with a mean of 4.7 inches and a standard deviation of 0.5 .Find the value of the quartile Q1

Answer 1

4.4

Explanation:

Quartile is 25%

From standard normal table, z-score is -0.6745

`Z=\frac {X-\mu}{\sigma}` where
`\mu` is mean
`\sigma` is standard deviation which is 0.5

`-0.6745=\frac {X-4.7}{0.5}`

X=4.7-0.33725=4.36275

The first quartile is approximately 4.4