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The mean weight of an adult is 68 kilograms with a standard deviation of 10 kilograms. If 128 adults are randomly selected, what is the probability that the sample mean would differ from the population mean by greater than 1.5 kilograms? Round your answer to four decimal places.

User Ishimwe
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Final answer:

To find the probability that the sample mean would differ from the population mean by greater than 1.5 kilograms, calculate the z-score and use the standard normal distribution table. The probability is 0.0.

Step-by-step explanation:

To find the probability that the sample mean would differ from the population mean by greater than 1.5 kilograms, we need to calculate the z-score for the given difference and then find the corresponding probability using the standard normal distribution table.

The formula to calculate the z-score is:

z = (x - μ) / (σ / √(n))

where:
x = sample mean difference (1.5 kg)
μ = population mean (68 kg)
σ = population standard deviation (10 kg)
n = sample size (128)

Substituting the given values, we get:
z = (1.5 - 68) / (10 / √(128))

Simplifying the equation, we get:
z = -6.5

Using the standard normal distribution table, we find that the probability of obtaining a z-score of -6.5 or greater is approximately 0.0. Therefore, the probability that the sample mean would differ from the population mean by greater than 1.5 kilograms is 0.0 (rounded to four decimal places).

User Gary Van Der Merwe
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