# Comparisons: Finding difference in data

Achievement Objectives
NA2-3: Know the basic addition and subtraction facts.
NA2-3: Know the basic addition and subtraction facts.
Specific Learning Outcomes

Recall addition and subtraction facts to 20.

Description of Mathematics

Number Framework Stage 5

Required Resource Materials
Activity

#### Using materials

Say: “Look at the graph above that some students have created. Build their graph with interlocking cubes if you need to, or use this presentation to find the differences between the preferred activities.”
Here are some questions to ask:

• “How many more students chose the beach than those who chose ice skating?”
• “How many more students chose the swimming pool than those who chose a day tramp?”
• “What is the difference between the number of students who wanted to go ice skating and the number who wanted to go to the swimming pool?”
• “Which activities had the same number of students wanting to do them?”

Examples: Comparison word problems and recording for: 8 + 3, 11 – 2, 7 – 3, 11 – 5, 7 + 3, 4 + 5, 10 – 8 …

#### Using imaging

Problem: Sam built a tower behind this screen, using two interlocking blocks. Matiu makes a tower six blocks higher than Sam’s. I am now building a second tower that is six blocks taller than Sam’s tower. How tall is the tower that Matiu built?

Examples: Comparison word problems and recording for: 12 – 4, 7 – 6, 11 – 2, 4 + 5, 2 + 11, 10 – 4 …

#### Using number properties

Examples: Comparison word problems and recording for: 28 + 6, 42 – 4, 71 – 6, 31 – 2, 44 + 5, 32 + 11, 60 – 4 …