stats

posted by .

The per capita consumption of coffee by people in the United States in a recent year was normally distributed, with a mean of 24.2 gallons and a standard deviation of 8.1 gallons.
What proportion of people in the U.S. drink more than 20 gallons of coffee a year?

  • stats -

    Use z-scores.

    Formula:
    z = (x - mean)/sd

    x = 20
    mean = 24.2
    sd = 8.1

    Plug the values into the formula and calculate z. Then check a z-table using the z-score for the proportion of people who drink more than 20 gallons.

    I hope this will help get you started.

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. statistics research

    What proportion of adults use between 15 and 23 gallons of gas per week if it is normally distributed with a mean of 16 gallons and a standard deviation of 5 gallons?
  2. statistics

    The U.S. Department of Agriculture claims that the mean consumption of coffee by the person in the United States is 24.2 gallons per year. A random sample of 120 people in the United States shows that the mean coffee consumption is …
  3. statistics

    what is the proportion of people who drink more than 20 gallons of cofffee per year if the mean is 24.2 gallons and the standard deviation is 8.1 gallons
  4. math

    Suppose the weekly use of gasoline for motor travel by adults in North America is approximately normally distributed, with a mean of 14 gallons and a standard deviation of 6 gallons. What proportion of adults use more than 18 gallons …
  5. economics 6

    Annual per capita consumption of milk is 21.6 gallons (Statistical Abstract of the United States: 2006). Being from the Midwest, you believe milk consumption is higher there and wish to support your opinion. A sample of 16 individuals …
  6. economics 6

    Annual per capita consumption of milk is 21.6 gallons (Statistical Abstract of the United States: 2006). Being from the Midwest, you believe milk consumption is higher there and wish to support your opinion. A sample of 16 individuals …
  7. economics

    Annual per capita consumption of milk is 21.6 gallons (Statistical Abstract of the United States: 2006). Being from the Midwest, you believe milk consumption is higher there and wish to support your opinion. A sample of 16 individuals …
  8. economics 6

    Annual per capita consumption of milk is 21.6 gallons (Statistical Abstract of the United States: 2006). Being from the Midwest, you believe milk consumption is higher there and wish to support your opinion. A sample of 16 individuals …
  9. Economics 6

    Annual per capita consumption of milk is 21.6 gallons (Statistical Abstract of the United States: 2006). Being from the Midwest, you believe milk consumption is higher there and wish to support your opinion. A sample of 16 individuals …
  10. Algebra

    The yearly per capita consumption of whole milk in the United States reached a peak of 40 gallons in 1945, at the end of World War II. By 1970 consumption was only 27.4 gallons per person. It has been steadily decreasing since 1970 …

More Similar Questions