Answer:
median = 17.5
Step-by-step explanation:
The median is the middle value of a data set arranged in ascending order. If there is not a middle value then the median is the average value of the numbers either side of the middle.
Data in ascending order is
8, 15, 17, 18, 19, 21
The median is between 17 and 18, hence
median =
= 17.5
Answer: B
Step-by-step explanation: Look at where the lines intersect
Answer:
D
Step-by-step explanation:
Answer:
b. Kathy
Step-by-step explanation:
We compare each of their score by how far away from the mean when in term of the standard deviation. Using the following formula
![\frac{x - \mu}{\sigma}](https://tex.z-dn.net/?f=%5Cfrac%7Bx%20-%20%5Cmu%7D%7B%5Csigma%7D)
For John he is (85 - 75)/5 = 2.
For Kathy she is (80 - 50)/10 = 3.
Since Kathy is 3 standard deviation better than her class' average, while John is only 2's. We conclude that Kathy did better.