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A doctor is studying heights of newborn babies. The doctor uses 20 inches as a reference point. Babies in the study receive a score to show how close they are to 20 inches. A baby that is 21 inches long receives a score of +1. A baby that is 18 inches long receives a score of .

User Rohunb
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2 Answers

2 votes

Answer:

-2 is ur answer:)

Explanation:

hope this helps:)

User Sachem
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3 votes

Answer:

A baby that is 18 inches long receives a score of -2.

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:


z_(score) = \displaystyle(x-\mu)/(\sigma)

A baby that is 21 inches long receives a score of +1.

Thus, we can write:


1 = \displaystyle(21-20)/(\sigma)\\\\\sigma = 1

We have to find z-score for baby that is 18 inches long.

Putting x = 18, we get:


z_(score) = \displaystyle(18-20)/(1) = -2

A baby that is 18 inches long receives a score of -2.

User Dr Alchemy
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