Practice

Effects of shifting, adding, & removing a data point - Questions

1. Chucky grabbed 11 items in the grocery store that each had a different price and had a mean cost of about \$ 4.44. On his way to the register, he gave in to an impulse to add a 12^{\text {th }} item: an entire wheel of cheese that cost \$ 39.99.

\begin{array}{ll}\text { Item } & \text { Cost } \\\hline \text { elephant garlic } & \$ 1.29 \\\text { Italian parsley } & \$ 1.92 \\\text { Kosher salt } & \$ 3.19 \\\text { bulgur wheat } & \$ 3.79 \\\text { matzoh meal } & \$ 3.99 \\\text { Anjou pears } & \$ 4.79 \\\text { tahini } & \$ 5.19 \\\text { mozzarella pearls } & \$ 5.29 \\\text { clam stock } & \$ 5.49 \\\text { rose water } & \$ 6.75 \\\text { beef tongue } & \$ 7.19 \\\text { gorgonzola cheese wheel } & \$ 39.99\end{array}

How will adding the wheel of cheese affect the mean and median?

Choose 1 answer:

(A) Both the mean and median will increase, but the median will increase by more than the mean.

(B) Both the mean and median will increase, but the mean will increase by more than the median.

(C) The mean will increase, and the median will decrease.

(D) The median will increase, and the mean will decrease.

2. Suzanne owns a small business that employs 5 other people. Suzanne makes \$ 100,000 per year, and the other 5 employees make between \$ 40,000 and \$ 50,000 per year.


Suzanne decides to leave the company and keep the other 5 salaries the same.


How will removing Suzanne's salary from the data set affect the mean and median?

Choose 1 answer:

(A) The mean will decrease and the median will increase.

(B) The median will decrease and the mean will increase.

(C) Both the mean and median will decrease, but the median will decrease more than the mean.

(D) Both the mean and median will decrease, but the mean will decrease more than the median.

3. A group of 4 friends likes to golf together, and each friend keeps track of her all-time lowest score in a single round. Their low scores are all between 90 and 100, except for Angie, whose low score is 80.

Angie then golfs a great round and has a new low score of 75.

How will decreasing Angie's low score affect the mean and median?

Choose 1 answer:

(A) Both the mean and median will decrease.

(B) The median will decrease, and the mean will stay the same.

(C) The mean will decrease, and the median will stay the same.

(D) The mean will decrease, and the median will increase.

4. A cat gave birth to 3 kittens who each had a different mass between 147 and 159 \mathrm{~g}. Then, the cat gave birth to a 4^{\text {th }} kitten with a mass of 57 \mathrm{~g}.

\begin{array}{lc}\hline \text { Kitten } & \text { Mass (in grams) } \\\hline \text { Archer } & 147 \\\hline \text { Nate } & 153 \\\hline \text { Lisa } & 159 \\\hline \text { Bob } & 57 \\\hline \end{array}

How will the birth of the 4^{\text {th }} kitten affect the mean and median?

Choose 1 answer:

(A) Both the mean and median will decrease, but the median will decrease by more than the mean.

(B) Both the mean and median will decrease, but the mean will decrease by more than the median.

(C) Both the mean and median will increase, but the median will increase by more than the mean.

(D) Both the mean and median will increase, but the mean will increase by more than the median.