Statistics Review

Given the probability model in the table below, what is the expected value of the random variable?

• 12

• 4.67

• 14

• 7.5

Tags

CCSS.HSS.MD.A.2

CCSS.HSS.MD.A.3

CCSS.HSS.MD.B.5

A small store keeps track of the number X of customers that make a purchase during the first hour that the store is open each day.  Based on the records, X has the following probability distribution.
The mean number of customers that make a purchase during the first hour that the store is open is:
   

• 2.0
• 2.5
• 2.9
• 3

Tags

CCSS.HSS.MD.A.2

CCSS.HSS.MD.A.3

Which number is not the mean, median, mode, or range of the data set 4, 3, 15, 11, 3, 8, 7, 5?

• 3
• 6
• 12
• 11

Tags

CCSS.6.SP.B.5C

What is the median of this data set?
3 , 17 , 17 , 11 , 8 , 13 , 5 , 18

• 11
• 12
• 13
• 17

Tags

CCSS.7.EE.B.3

What is the interquartile range (IQR)?

• 4
• 64
• 60
• 8

Tags

CCSS.6.SP.A.1

CCSS.6.SP.A.2

CCSS.6.SP.A.3

CCSS.6.SP.B.5

Which class has the higher test score median? 

• Class #1
• Class # 2 
• The medians are equal
• The median is not shown here. 

Tags

CCSS.6.SP.A.1

CCSS.6.SP.A.2

CCSS.6.SP.A.3

CCSS.6.SP.B.5

If 75 people were surveyed.. how many people spent $100 or more on groceries per week?

• 38

• 19

• 57

• 75

Calculate the interquartile range of the following 20 scores

2, 3, 5, 7, 9, 11, 15, 17, 19, 20, 20, 21, 23, 30, 31, 32, 33, 35, 37, 40

• 38
• 20.5
• 17
• 21.5

Tags

CCSS.6.SP.B.5C

The data set below has an outlier of 42.
2, 5, 12, 15, 19, 4, 6, 11, 16, 18, 12, 12, 42
What effect does removing the outlier have on the distribution of the data?

• The mean will decrease
• The median will decrease
• The mean will increase
• The median will increase

Tags

CCSS.6.SP.A.2

CCSS.6.SP.A.3

CCSS.6.SP.B.5

Is the dot plot skewed left, right, or symmetric?

• skewed left

• skewed right

• symmetric