1. The problem involves a normal distribution with mean $\mu = 15.7$ and standard deviation $\sigma = 0.7$. We want to find the probability that a value is less than $15.2$ (the cutoff point).
2. The formula to standardize a value $x$ in a normal distribution is the z-score formula:
$$z = \frac{x - \mu}{\sigma}$$
This converts the value to a standard normal distribution with mean 0 and standard deviation 1.
3. Calculate the z-score for $x = 15.2$:
$$z = \frac{15.2 - 15.7}{0.7} = \frac{-0.5}{0.7} = -\frac{5}{7} \approx -0.7143$$
4. The z-score tells us how many standard deviations $15.2$ is below the mean.
5. To find the probability that a value is less than $15.2$, we look up the cumulative probability for $z = -0.7143$ in the standard normal distribution table or use a calculator.
6. Using a standard normal table or calculator, $P(Z < -0.7143) \approx 0.2375$.
7. Therefore, the probability that a value from this distribution is less than $15.2$ is approximately $0.2375$ or 23.75%.
Normal Distribution 8E1C0E
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