Statistics

What is a z-score?

What is a z-score? Learn the core idea, common steps, and how to recognize this statistics concept in homework problems.

Problem Statement

What is a z-score?

Step-by-step solution

Problem Statement

What is a z-score?

Step-by-Step Explanation

A z-score tells how many standard deviations a value is from the mean.

  1. Identify what the question is asking. In Statistics, this usually means naming the known quantities, the unknown quantity, and the concept that connects them.
  2. Write the relevant definition, rule, or relationship before substituting numbers or manipulating symbols.
  3. Work one step at a time and keep units, signs, and restrictions visible.
  4. Check whether the answer makes sense in the original context.

Key Formula

z=xμσz=\frac{x-\mu}{\sigma}

Final Answer

A z-score tells how many standard deviations a value is from the mean. The reliable strategy is to start from the definition, apply the correct rule carefully, and then interpret the result in plain language.