Statistics — Quiz 2

Questions in this quiz (9)

1. The 6 positive integers $$x,x,x,y,y,z$$ have an average of $$x$$. What is the value of $$\frac{y+z}{2}$$?

   • $$\frac{2x - y}{2}$$
   • $$\frac{x - y}{2}$$
   • $$\frac{3x - y}{2}$$
   • $$3x - y$$

2. Maya decided to improve her writing scores by taking four practice tests with her coach. On the second test, she scored 10 points higher than her first test score. On the third test, she scored 20 points higher than her first test score, and on the fourth test, she scored 30 points higher than her first test score. If the average score of the four tests was 70, what was her score on the third test?

   • 75
   • 70
   • 85
   • 90

3. David has a list of 11 integers with median $$n$$. He adds the numbers $$n+15$$ and $$n-15$$ to the list. Then, all numbers in the list are multiplied by 3. What is the new median?

   • $$n$$
   • $$3n$$
   • $$3n+45$$
   • $$3n-45$$

4. A set of 50 donations to a charity event from a local community are shown in the table below. Which donation range contains the median of the donations?

   • $$1-50$$
   • $$51-100$$
   • $$101-500$$
   • $$501-1000$$

5. Jessica tracks the number of cookies she bakes each day for a week. On Monday, she bakes 20 cookies, on Tuesday 18 cookies, on Wednesday 22 cookies, and on Thursday 18 cookies. She wants to calculate the mean, median, and mode of her weekly cookie production. If Jessica bakes 19 cookies on Friday, how will this impact the statistical measures?

   • The mode will increase.
   • The median will stay the same.
   • The median will decrease.
   • The mean will increase.

6. Linda plays a word puzzle five times. Her scores are $$20$$ points, $$30$$ points, $$25$$ points, and $$15$$ points in the first four games. How many points must Linda score in her fifth game for the mean, median, and mode of her five scores to be equal?

   • $$35$$
   • $$30$$
   • $$25$$
   • $$40$$

7. A shipping company tracks the number of packages processed each day for one week. The model curve represents an equation that best fits the actual data. The graph below shows the actual and model values. For the week shown in the graph, what was the median number of packages processed per day?

   • 90
   • 60
   • 80
   • 70

8. A data set consists of 5 integers with the following properties:The mean is 10.The median is 11.The mode is 12.Which of the following statements represents the data set?

   • $$10, 11, 11, 12, 12$$
   • $$4, 11, 11, 12, 12$$
   • $$10, 11, 11, 12, 15$$
   • $$10, 10, 11, 12, 12$$

9. The members of a data set are listed below. A new data set is created from the original data set by adding integers $$x, y,$$ and $$z$$, where:$$x \leq 20$$$$y \leq x$$$$z \geq 40$$What is the median of the new data set?Original Data Set:$$12, 18, 22, 26, 30, 30, 38$$

   • $$26$$
   • $$22$$
   • $$24$$
   • $$20$$