Questions: Complete the statement. Round your answer to the nearest thousandth. In a population that is normally distributed with mean 29 and standard deviation 3, the top 31% of the values are those greater than .

Complete the statement. Round your answer to the nearest thousandth.
In a population that is normally distributed with mean 29 and standard deviation 3, the top 31% of the values are those greater than .
Transcript text: Complete the statement. Round your answer to the nearest thousandth. In a population that is normally distributed with mean 29 and standard deviation 3, the top $31 \%$ of the values are those greater than $\square$ .
failed

Solution

failed
failed

Solution Steps

Step 1: Determine the Z-Score for the 69th Percentile

To find the value above which the top \(31\%\) of the values lie, we first need to calculate the z-score corresponding to the \(69\)th percentile of the normal distribution. The z-score is given by:

\[ z = 0.4959 \]

Step 2: Convert the Z-Score to the Actual Value

Next, we convert the z-score to the actual value in the distribution using the formula:

\[ X = \mu + z \cdot \sigma \]

where:

  • \(\mu = 29\) (mean)
  • \(\sigma = 3\) (standard deviation)

Substituting the values, we have:

\[ X = 29 + 0.4959 \cdot 3 \]

Calculating this gives:

\[ X = 29 + 1.4877 = 30.4877 \]

Rounding to the nearest thousandth, we find:

\[ X \approx 30.488 \]

Final Answer

The value above which the top \(31\%\) of the values lie is

\[ \boxed{30.488} \]

Was this solution helpful?
failed
Unhelpful
failed
Helpful