Question

Use technology or a z-score table to answer the question.

The weights of members of a baseball league are normally distributed with a mean of 176 pounds and a standard deviation of 11.4 pounds. Consider a league membership of 120 members.
How many of the members will weigh 165 pounds or more?
A.)67
B.)76
C.)80
D.)100

Answer 1

D. 100

Explanation:

1. Find the z-score: 165-176/11.4 = -1.2

2. Find the percentage of the z-score. Here it's 16.85%

3. Because we are searching for the amount of members that weigh MORE than 165 pounds and not LESS, we need to find the greater percentage by subtracting 16.85% from 100% which is 83.15%. This is the percentage of people that weigh more than 165 pounds.

4. Multiply the percentage by the number of members: 83.15%*120 = 99.78

5. Round it to a whole number because someone can't be 0.78 of a person. You get 100 members.

Also, I took the test :)