MathematicsBeginner

Adding and subtracting whole tens

See whole tens as groups of ten

Estimated time · 6 min 9 Content blocks

Core concepts

Formulas

30+40=70,80−50=3030+40=70,\qquad 80-50=30

Worked example

Example
Solution

Worked example

Worked examples
Example
Solution steps
  1. 1
  2. 2
  3. 3
  4. 4
Answer

Worked example

Worked examplesVariant 1
Example
Solution steps
  1. 1
  2. 2
  3. 3
  4. 4
Answer

Worked example

Worked examplesVariant 2
Example
Solution steps
  1. 1
  2. 2
  3. 3
  4. 4
Answer

Exercises

Fill in the blank

Prerequisites

Counting and place value to 1007 min
Practice set
Answered 0 / 6
1Fill in the blank

Tip

2Fill in the blank

Tip

3Fill in the blank

Tip

4True / False

Tip

5Single choice

Tip

6Fill in the blank

Tip

Results are not saved — this session disappears when you leave.
AI DO LEARN

Science, made explorable.

5 Disciplines·6 Levels·647 Knowledge points

© 2026 AI DO LEARN. All rights reserved.

Original explanations, diagrams and code may not be republished without permission; please credit the source when quoting.