Question

Suppose X∼B(75,0.28)

- For this distribution, is the normal approximation reasonable? Your answer must make reference to skewness.
- If you take a sample of size 120, what's the approximate probability that the proportion of successes will be larger than 0.65? (Answer this regardless of your answer to a.)

Answer #1

Let b be 59. Let c be 67. Suppose X∼B(59,0.67).
For this distribution, is the normal approximation reasonable?
Your answer must make reference to skewness.
If you take a sample of size 120, what's the approximate
probability that the proportion of successes will be larger than
0.65? (Answer this regardless of your answer to a.)

Use the normal approximation to find the indicated probability.
The sample size is n, the population proportion of successes is p,
and X is the number of successes in the sample.
n = 87, p = 0.72: P(X > 65)
Group of answer choices
0.7734
0.2266
0.2483
0.2643

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