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Ratios and Data 6-8 / Week 10 / Thursday
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Week 10 · Statistical Questions

Thursday

The Field Day survey
// Questions with many answers, and the pictures that show them
⏱ about 20 min

Thursday: The Field Day Survey

Raven drops a stack of tally sheets on the Numbers Desk. "Twenty kids answered. How many Field Day games would you play?"

Rocket flips through them. "Someone said 8! And someone said 2. Those cannot both be right."

"They are both data," Raven says. "What do you notice about where most of the answers land?"

Nova draws a number line in the air. "Place them before you decide."

Rocket stacks the dots. A peak rises at 4. "Most kids said 4. Then 3 and 5. Nobody said 7."

"A peak at 4, a gap at 7, two kids far out at 8," Raven says. "That is the shape."

Rocket taps the peak. "So I build about 4 games, with a bonus round for the 8 kids?"

Nova blinks. "Now you are reading data."

The crew's survey data

Raven asked 20 kids on the street. A grown-up stood with her at each door. She wrote down only the number, never who said it.

Here are the answers in order from least to greatest, and then as a count for each answer.

Kid 1 to 10Kid 11 to 20
2, 3, 3, 3, 3, 4, 4, 4, 4, 44, 5, 5, 5, 5, 6, 6, 6, 8, 8
Answer (games)How many kids said it
21
34
46
54
63
82
A dot plot of the Field Day survey from 2 to 8, peaking at 4 with a gap at 7.

Describe the shape

  • Peak: the tallest stack is at 4 games, with 6 kids.
  • Cluster: most dots sit between 3 and 6. That is where the typical answers live.
  • Gap: no kid said 7.
  • Far out: two answers sit at 8, away from the cluster. Values like that are worth a second look.

Reporting a data set means saying three things. How many answers you collected, what you measured, and what shape you saw.

Here: 20 kids, and the games they would play. The peak is at 4, with a cluster from 3 to 6 and two far out at 8.

Say it that way and anyone can picture the data without seeing the plot. That is the goal of a report.

The histogram below groups the answers in bins two games wide. The 4 to 5 bar towers over the rest.

A histogram of the Field Day survey with bins two games wide; the 4 to 5 bar is tallest.
READ THE SURVEY
  • Read the question.
  • Tap your answer.
A dot plot of the Field Day surveyHow many kids said 5 games or more?
A dot plot of the Field Day surveyHow many kids said fewer than 4 games?
Where is the gap in this data?
A histogram of the Field Day surveyHow many kids are in the 4 to 5 bar of the histogram?
How many kids said exactly 4 games? Type the number.
WHY THIS EXERCISEThe peak tells Rocket the most common wish, which helps him plan the number of games.
The least answer was
The greatest answer was
The number of kids surveyed was
WHAT SHOULD ROCKET BUILD?
  • Read the question.
  • Tap your answer.
Rocket wants the number of games most kids asked for. Which shape word should he look at?
Two kids said 8 games. What should the crew do with those answers?
A kid who did not answer should be:
Try it
Say one sentence about this data that uses the words peak, cluster and gap.
Then say what you would tell Rocket to build. Use the data, not a guess.

You described a real distribution with real shape words. Tomorrow you meet the box plot and review the week.

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