The mean number of text messages sent per month by customers of a ...

[Haya94]

The mean number of text messages sent per month by customers of a cell phone service provider is 1,850, and the standard deviation is 800. Find the z-score associated with 3,000 messages sent.
  1. z = 2.75x
  2. z = 1.44
  3. z = 1.44
  4. z = 1.19
  5. z = 40.66

Question 2

Suppose that the distribution of weekly water usage for single-family homes in a particular city is mound shaped and approximately symmetric. The mean is 1,300 gallons, and the standard deviation is 200 gallons.
 
   What is the approximate value
   of the 98th percentile?

  1.1,700 gallons
  2.1,100 gallons
  3.1,500 gallons
  4.1,900 gallons
  5.1,300 gallons

[vkodali]

Answer to Question 1

2

Answer to Question 2

1

[Haya94]

Thank you!

[vkodali]

Always glad to help...