Question

A car manufacturer crash tests a certain model of car and measures the impact force. The test and model in question produce impact forces that are normally distributed with a mean of 303030 metric tons and a standard deviation of 1.51.51, point, 5 metric tons. Suppose that the manufacturer tests a random sample of 444 cars and calculates the sample mean impact force.

Answer 1

Answer:

30

Step-by-step explanation:

Given :

Mean, m = 30 metric tons

Standard deviation (s) = 1.5 metric ton

Sample size, n = 4

Since the impact force in the test model is normally distributed, the shape of the sampling distribution will also be approximately normal with a mean equal to the mean of the test model.

Hence, the sample mean impact force will be equal to the population mean.

Therefore, sample mean = 30 ; population mean = 30

Answer 2

Answer:

  _

P(x >30.75)≈0.16

Step-by-step explanation:

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