Math Problem Statement

Daily Caloric Intake According to one source, people eat on average 3540calories per day. If the standard deviation is 325calories, find the z score for each raw score. Round z scores to at least two decimal places.

The z score corresponding to 3320 calories is

Solution

To find the z-score corresponding to a raw score, we use the z-score formula:

z=Xμσz = \frac{X - \mu}{\sigma}

Where:

  • XX = raw score (3320 calories)
  • μ\mu = mean (3540 calories)
  • σ\sigma = standard deviation (325 calories)

Now substitute the values:

z=33203540325z = \frac{3320 - 3540}{325}

z=220325=0.6769z = \frac{-220}{325} = -0.6769

Rounding to two decimal places:

z=0.68z = -0.68

Thus, the z-score corresponding to 3320 calories is -0.68.

Would you like further details or have any questions?

Here are five related questions:

  1. What is the interpretation of a negative z-score?
  2. How would the z-score change if the raw score were higher than the mean?
  3. What is the probability associated with this z-score?
  4. How do you compute the z-score for a raw score of 3800 calories?
  5. How does the standard deviation affect the spread of z-scores?

Tip: The z-score tells you how many standard deviations a raw score is from the mean.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Statistics
Z-scores
Standard Deviation
Mean

Formulas

z = (X - μ) / σ

Theorems

Z-score theorem (Standard Normal Distribution)

Suitable Grade Level

Grades 10-12