In forest, the average number of maples was 20 trees/plot with a standard deviation of 7...

In forest, the average number of maples was 20 trees/plot with a standard deviation of 7 trees/plot. If we take a sample of eight plots, what is the probability that the mean of this sample will be between 18 and 21?

Assuming the octane ratings are normally distributed, use the octane ratings data to construct a 95% confidence interval for the mean octane rating.

We want to test how accurate an optical character recognition (OCR) device is. We collect a sample of 500 handwritten words and find out that 440 were read correctly. Construct a 95% confidence interval for the population proportion.

We want to see what proportion of seeds will germinate. We plant 200 seeds and see that 194 germinate. Construct a 95% confidence interval for the population proportion.

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orchestra answered 1 year ago

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