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“Given that X is normally distribution with mean of 32.5 and standard deviation of 3.8”

To 3 decimal places if:

“Given that X is normally distribution with mean of 32.5 and standard deviation of-example-1
User Thanasis M
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Answer:

To solve for the value of "k" in each scenario, you can use the standard normal distribution table (z-table) or a calculator. Here are the steps to find the values of "k" for each case:

A. For \( P(X > k) = 0.4325 \):

- Find the z-score corresponding to \( 1 - 0.4325 = 0.5675 \) in the z-table.

- The z-score is approximately 0.18.

- Use the z-score formula: \( z = \frac{x - \mu}{\sigma} \) to solve for "x" (the value of "k").

- Plug in the given values: \( 0.18 = \frac{k - 32.5}{3.8} \) and solve for "k".

B. For \( P(X \leq k) = 0.854 \):

- Find the z-score corresponding to \( 0.854 \) in the z-table.

- The z-score is approximately 1.04.

- Use the z-score formula: \( z = \frac{x - \mu}{\sigma} \) to solve for "x" (the value of "k").

- Plug in the given values: \( 1.04 = \frac{k - 32.5}{3.8} \) and solve for "k".

C. For \( P(30 < X < k) = 0.5635 \):

- Find the z-scores corresponding to \( 0.5 - \frac{0.5635}{2} = 0.21725 \) and \( 0.5 + \frac{0.5635}{2} = 0.78275 \) in the z-table.

- The z-scores are approximately -0.78 and 0.69.

- Use the z-score formula: \( z = \frac{x - \mu}{\sigma} \) to solve for "x" (the values of "k" for both ends).

- Plug in the given values and solve for "k".

Remember to solve for "k" in each case and then round your answer to 3 decimal places.

User Romanos
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