To find $P(2.8 < X < 5)$, you would need more information about the distribution of $X$. Here are the possible scenarios:

1. If $X$ follows a normal distribution:
   If $X \sim N(\mu, \sigma^2)$, you would need the mean $\mu$ and standard deviation $\sigma$ to calculate the probability. You would use the z-score formula: $z = \frac{X - \mu}{\sigma}$ Then, you would find the corresponding probability using the standard normal table or a calculator.

2. If $X$ follows a uniform distribution between 2.8 and 5:
   In this case, $P(2.8 < X < 5) = 1$ because $X$ lies entirely within this interval.

3. If $X$ follows any other distribution:
   You'd need the specific distribution details or a probability density function (PDF) to calculate $P(2.8 < X < 5)$.

Could you provide more details about the distribution of $X$? This will help in finding the exact probability.

Would you like additional guidance on probability with different distributions?

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Related Questions

1. How can I calculate probabilities for a normal distribution?
2. What is a z-score, and how is it used in probability calculations?
3. How do probabilities work in a uniform distribution?
4. What are some common types of probability distributions?
5. How do I interpret cumulative probability values?

Tip: When working with probabilities, always confirm the type of distribution first, as the approach changes significantly.