Asksia AI LOGO

Sia

Question
Math
Posted 10 months ago

The grades on a math midterm at Springer are roughly symmetric with μ=72\mu=72 and σ=4.5\sigma=4.5.

Stephanie scored 86 on the exam.
Find the z-score for Stephanie's exam grade. Round to two decimal places.
Sign in to unlock the answer
Answer from Sia
Posted 10 months ago
Solution by Steps
step 1
Calculate the difference between Stephanie's score and the mean
$z = \frac{X - \mu}{\sigma}$ where $X = 86$, $\mu = 72$, and $\sigma = 4.5$.
step 2
Substitute the given values into the z-score formula
$z = \frac{86 - 72}{4.5}$
step 3
Perform the subtraction in the numerator
$z = \frac{14}{4.5}$
step 4
Divide the numerator by the denominator to find the z-score
$z = 3.111111111111111$
step 5
Round the z-score to two decimal places
$z \approx 3.11$
[1] Answer
z=3.11z = 3.11
Key Concept
Z-score Calculation
Explanation
The z-score represents how many standard deviations an element is from the mean. It is calculated by subtracting the mean from the value and then dividing by the standard deviation.

Not the question you are looking for? Ask here!

Enter question by text

Enter question by image

Unlock Smarter Learning with AskSia Super!

Join Super, our all-in-one AI solution that can greatly improve your learning efficiency.

30% higher accuracy than GPT-4o
Entire learning journey support
The most student-friendly features
Study Other Question