D. Data · Data and Probability

Data and Probability: Unit Review

D1.1 D1.2 D1.3 D1.4 D1.5 D2.1 D2.2 A1About 40 minutes

Learning goals

I can sort, collect, organize and show data in many ways.
I can find the mode and use data to make decisions.
I can describe how likely events are and make predictions.

Words to know

Carroll diagram
A sorting grid. Every item goes in exactly one box.

Venn diagram
Overlapping circles for sorting. Things that fit both labels go in the middle.

two-way tally table
A tally table with rows and columns for two pieces of information.

mode
The answer that appears most often.

complementary events
An event and its opposite. One of them always happens.

population
The whole group you collect data from.

Let's review!

You have become a real data detective! This review has a few questions from every lesson in the unit. Try each one, then press Show answer to check. If a part feels tricky, go back to that lesson for more practice.

The four places in a Venn diagram: each circle by itself, the middle for both labels, and the space outside for neither.

The likelihood line from impossible to certain, with an example for each word from the unit.

Sorting by Two Attributes: Tables and Carroll Diagrams

Shapes are sorted by Red / Not red and Circle / Not a circle. Where does a red triangle go?

A Carroll diagram has 3, 5, 1 and 4 items in its boxes. How many items were sorted?

Where does a bat go: Has fur / No fur and Can fly / Cannot fly?

Sorting with Venn Diagrams

Labels: Red and Fruit. Where does a cherry go?

Venn diagram: skating only 4, both 3, skiing only 2, neither 1. How many like skating?

Same Venn diagram. How many were asked?

Collecting Data with Two-Way Tally Tables

How many does this tally show: two bundles of 5 and 4 more?

Which way of collecting data is it? You flip a loonie 20 times and record heads or tails.

Two-way table: Apple: kids 6, grown-ups 3. Grapes: kids 4, grown-ups 5. How many grown-ups were asked?

Same table. How many people chose apple?

Showing Data: Pictographs, Line Plots and Bar Graphs

What 3 parts must every graph have?

Which graph uses an X above a number for each answer?

Data: dogs 5, cats 3. In a bar graph with one square for each child, how tall is the cat bar?

Finding the Mode

What is the mode? 2, 4, 4, 5, 4, 2

What is the mode? toque, scarf, toque, scarf, mitts

What is the mode? red, blue, green

A line plot has 3 Xs above 1, 2 Xs above 2, and 5 Xs above 3. What is the mode?

Data Detectives: Asking Questions and Making Decisions

Votes: library 6, gym 10, art 8. How many more votes did gym get than art?

Same votes. How many children voted in all?

Same votes. Write a convincing argument for a decision.

Impossible, Possible, Certain: Events and Their Opposites

What is the opposite of it snows tomorrow?

A bag has only red counters. How likely is pulling red? Not red?

A spinner has 1 blue part and 3 green parts. Which is more likely: blue or not blue?

Will Another Group Have the Same Mode?

What is a population?

Your class's favourite snack mode is popcorn. Predict the mode for another Grade 2 class at your school. Give a reason.

How do you test that prediction?

Just for fun

Why did the spinner feel dizzy?

It spent the whole day going around in circles! 🌀

How to use this review

Let your child try each set without looking at the lesson first.
Use real objects (socks, blocks, crayons) for sorting questions and paper for tallies and graphs.
After each set, check the answers together and ask, "How did you figure that out?"
If two or more questions in a set were tricky, go back to that lesson's examples before the quiz.
Short and cheerful is best. You can split this review over two days.

Check your understanding

Quiz

Shapes are sorted by Blue / Not blue and Square / Not a square. Where does a yellow square go?

In a Venn diagram, where does something go if it fits neither label?

Venn diagram: dog only 2, both 3, cat only 4, neither 1. How many have a cat?

How many does this tally show: three bundles of 5 and 1 more?

Which graph is best for answers that are numbers, like How many teeth have you lost?

What is the mode? 3, 1, 3, 2, 3, 1

Votes: skating 9, sledding 6, skiing 5. How many fewer votes did skiing get than skating?

If an event is certain, its opposite is...

A spinner is half red and half blue. Landing on red is...

10.

Your class's mode is summer. Another Grade 2 class at your school will...

For parents and teachers

What this review covers: the whole Data and Probability unit: sorting by two attributes in tables, Carroll and Venn diagrams (D1.1), collecting data in two-way tally tables (D1.2), graphs with one-to-one correspondence (D1.3), the mode (D1.4), analysing data and making decisions (D1.5), likelihood of an event and its opposite (D2.1), and predicting the mode for another population (D2.2).

Which lesson to revisit:

Putting items in the wrong box, or checking only one attribute: go back to Sorting by Two Attributes.
Forgetting the middle of a Venn diagram, or leaving out items that fit neither label: go back to Sorting with Venn Diagrams.
Miscounting tally bundles, tallies in the wrong column, or mixing up interview, observation and experiment: go back to Collecting Data with Two-Way Tally Tables.
Graphs with uneven pictures, a scale that doesn't start at 0, or missing title, labels or source: go back to Showing Data.
Giving the biggest number instead of the most common answer, or missing ties: go back to Finding the Mode.
Mixing up how many more and how many in all, or decisions with no reason: go back to Data Detectives.
Calling a likely event certain, or confusing an event with its opposite: go back to Impossible, Possible, Certain.
Saying another group will definitely have the same mode: go back to Will Another Group Have the Same Mode?

Quiz guide: questions 1 to 3 are sorting (Carroll and Venn); question 4 is tallies; question 5 is graphs; question 6 is the mode; question 7 is analysing data; questions 8 and 9 are likelihood; question 10 is predicting the mode for another population.

How to help: redo one example from the lesson with real objects, then try a similar question. Praise explanations that use because and a number from the data.