Ask Question
30 August, 16:32

How can you use the mean and standard deviation of a data set to fit it to a normal distribution and to estimate population percentages?

+5
Answers (1)
  1. 30 August, 16:41
    0
    We use the mean and standard deviation to standardising a value, in other words, to find the z-score. In a normally distributed data, the value of mean, μ, represent 50% of the population.

    A z-score will allow us to 'read' the probability on a z-table

    For example, we have a normally distributed data with mean 12 and standard deviation 2.1. We can evaluate the probability of any given value, X, by finding the z-score then reading the score on the z-table. Say that we want to find the probability when X < 15.

    The standardising formula is (X-μ) / σ

    Where μ is the mean and σ is the standard deviation

    Using μ and σ from our example, we have

    z-score = (15-12) / 2.1 = 1.43 (rounded to two decimal places)

    p-value is P (z<1.43) = 0.9236

    The value 0.9326 is a probability value, and as percentage, it's 93.26
Know the Answer?
Not Sure About the Answer?
Find an answer to your question 👍 “How can you use the mean and standard deviation of a data set to fit it to a normal distribution and to estimate population percentages? ...” in 📗 Mathematics if the answers seem to be not correct or there’s no answer. Try a smart search to find answers to similar questions.
Search for Other Answers