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You did these with your group. Now do them on your own — the model above is yours to copy.

1. 1

   Same stepsFinish what the group started. Use the model above, step for step.

   Try it together — then prove it: New data set, out of order: 13, 3, 7, 10, 7. Put it in order first. In order: 3, 7, 7, 10, 13. Five values, so the middle is the 3rd. The median is 7. Say what it means: a typical value in this set is about 7. Now change the 13 to 130. Does the median move? It does not — still 7. That resistance is exactly why the median is used. Now prove it: say why that move had to work at all — not just that it did.

   Show your work
2. 2

   Warm restartA histogram bar for the interval 10–19 has a height of 6. How many data values fall in that interval?

   1. A6
   2. B10
   3. C19
   4. D16

   How do you know?
3. 3

   Warm restartA histogram uses the intervals 0–9, 10–19 and 20–29. What is the width of each interval?

   1. A10
   2. B9
   3. C3
   4. D29

   How do you know?
4. 4

   Warm restartA histogram has bar heights 3, 7, 5 and 2. How many data values are in the whole set?

   1. A17
   2. B7
   3. C4
   4. D15

   How do you know?

You answered these out loud. Now write them.

Answer, then say how you know — the reason is the part that counts.

1. 5

   Think it throughThe teacher said 'most students scored around 87.' Which measure is that?

   1. AThe mean (average)
   2. BThe mode
   3. CThe median
   4. DThe range

   Why is that the answer?
2. 6

   Think it throughThe student said 'the most common score was 92.' Which measure is that?

   1. AThe mode
   2. BThe mean
   3. CThe median
   4. DThe range

   How do you know? Give a second reason as well.
3. 7

   Think it throughWhat is the median of the 10 scores?

   1. A88
   2. B87
   3. C92
   4. D86.6

   Explain your thinking. What would have to change for a different choice to be right?
4. 8

   Back to the modelThe mean (43) is higher than the median (41). Why? Which better represents a typical game?

Use the words

Fill each blank with a word from the bank.

• When one value sits far from the rest, describe the typical value with the ___.
• The middle value of a data set when the numbers are in order is the ___.
• The value that appears most often in a data set is the ___.
• A value that is much larger or smaller than the rest of the data is an ___.

Explain the thinking

1. 9

   Find the mistakeAnother student made this exact mistake in this lesson. Explain why it is wrong, then write what they should have done.

   The mistake: A common mistake in Mean, Median, and Mode is finding the median without ordering the data first — students pick the middle number straight from the list as given (for 9, 4, 7, 2, 6 they say the median is 7, the middle position in that original order) instead of sorting least to greatest (2, 4, 6, 7, 9) and finding the true middle value, 6.
2. 10

   Say moreAfter ordering the scores on the number line, how do you find the median, and how is it different from the mean you calculated?
3. 11

   Write your ownWrite your own problem about this situation, then solve it and show the answer. The situation: Some students surveyed the teachers at their school about their years of teaching experience. The data they collected is shown.

   Show your work

Last check

These two come from Lesson 2.2. If they are shaky, that is the lesson to revisit — not this one.

1. 12

   Show what you knowExplain your thinking — Data set: 4, 7, 10, 7, 12. What is the median, and what does it tell you?

   1. A7 — a typical value in this set is about 7
   2. B10 — it is the middle number as the list is written
   3. C8 — it is the average of all five values
   4. D12 — it is the largest value

   Explain your choice.
2. 13

   From Lesson 2.2Explain your thinking — A histogram of player heights shows: 60–63 in: 2, 64–67 in: 7, 68–71 in: 9, 72–75 in: 4. Which interval has the most players?

   1. A72–75 inches
   2. B60–63 inches
   3. C68–71 inches
   4. D64–67 inches

   How do you know?
3. 14

   From Lesson 2.2Does the histogram support the coach's claim?

   1. AYes — 18 of 23 players cluster in the middle intervals
   2. BNo — most players take 0–2 shots
   3. CNo — the data is skewed right
   4. DYou cannot tell from a histogram

   How do you know?

Be honest — this tells your teacher what to do next