"A study examining people's water consumption estimated men spend an average of 10.4 minutes taking a shower, with a standard deviation of 4.8 minutes (Shimokura et al., 1998)." What percentage of men spend between 10 and 20 minutes taking a shower?

Question

Quizplus · Accepted Answer

To find the percentage of men who spend between 10 and 20 minutes taking a shower, first we need to convert these values to z-scores using the formula: z = (x - μ) / σ where x is the time in minutes, μ is the mean time (10.4), and σ is the standard deviation (4.8).

For x = 10 minutes, z = (10 - 10.4) / 4.8 = -0.08. 
For x = 20 minutes, z = (20 - 10.4) / 4.8 = 1.96.

We can then use a standard normal distribution table or calculator to find the area (or percentage) under the curve between these two z-scores. This area represents the percentage of men who spend between 10 and 20 minutes taking a shower.

Using a calculator, we find that the area between z = -0.08 and z = 1.96 is approximately 0.5091, or 50.91%. Therefore, the correct answer is choice C.

"A Study Examining People's Water Consumption Estimated Men Spend an Average