Question

7. A standardized​ exam's scores are normally distributed. In a recent​ year, the mean test score was 21.4 and the standard deviation was 5.6.

The test scores of four students selected at random are 13, 23, 9​, and 37. Find the​ z-scores that correspond to each value and determine whether any of the values are unusual.

The​ z-score for 13 is __. ​(Round to two decimal places as​ needed.)

The​ z-score for 23 is __. ​(Round to two decimal places as​ needed.)

The​ z-score for 9 is __.

​(Round to two decimal places as​ needed.)

The​ z-score for 37 __.

​(Round to two decimal places as​ needed.)

Which​ values, if​ any, are​ unusual? Select the correct choice below​ and, if​ necessary, fill in the answer box within your choice.

A.The unusual​ value(s) is/are ___.

​(Use a comma to separate answers as​ needed.)

B.None of the values are unusual.

8. Find the indicated area under the standard normal curve.

To the right of z=2.78

The area to the right of z=2.78 under the standard normal curve is ___.

9. Find the indicated probability using the standard normal distribution.

​P( -1.05 <z<0​)=___.

13. A vending machine dispenses coffee into a sixteen​-ounce cup. The amount of coffee dispensed into the cup is normally distributed with a standard deviation of 0.04 ounce. You can allow the cup to overfill 3% of the time. What amount should you set as the mean amount of coffee to be​ dispensed?

___ ounces.

Answer 1