Answer:
A baby that is 18 inches long receives a score of -2.
Step-by-step explanation:
We are given the following information in the question:
The doctor uses 20 inches as a reference point.
Mean, μ = 20 inches
We assume that the distribution of heights of newborn babies is a bell shaped distribution that is a normal distribution.
Formula:
[tex]z_{score} = \displaystyle\frac{x-\mu}{\sigma}[/tex]
A baby that is 21 inches long receives a score of +1.
Thus, we can write:
[tex]1 = \displaystyle\frac{21-20}{\sigma}\\\\\sigma = 1[/tex]
We have to find z-score for baby that is 18 inches long.
Putting x = 18, we get:
[tex]z_{score} = \displaystyle\frac{18-20}{1} = -2[/tex]
A baby that is 18 inches long receives a score of -2.
Answer:
-2 is ur answer:)
Step-by-step explanation:
hope this helps:)
