1. **Problem Statement:**
We are given a normal distribution and need to find the z-score that corresponds to the lowest 23% of the data values and then find the data value associated with that z-score.
2. **Formula and Explanation:**
The z-score formula is:
$$z = \frac{x - \mu}{\sigma}$$
where $x$ is the data value, $\mu$ is the mean, and $\sigma$ is the standard deviation.
The z-score tells us how many standard deviations a data point is from the mean.
3. **Finding the z-score for the lowest 23%:**
The lowest 23% corresponds to the 0.23 quantile of the standard normal distribution.
Using a z-table or calculator, the z-score for 0.23 cumulative probability is approximately:
$$z \approx -0.74$$
4. **Finding the data value associated with this z-score:**
Rearranging the z-score formula to solve for $x$:
$$x = z \times \sigma + \mu$$
Since the problem does not provide $\mu$ and $\sigma$, we leave the answer in terms of these variables:
$$x = -0.74 \times \sigma + \mu$$
This means the data value at the 23rd percentile is $0.74$ standard deviations below the mean.
**Final answers:**
- The z-score for the lowest 23% is approximately $-0.74$.
- The data value corresponding to this z-score is $x = -0.74 \sigma + \mu$.
Normal Curve Zscore 98A884
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