7.2.1
Missing Number Problems
Writing Missing Number Problems
Writing Missing Number Problems
To work out missing numbers in problems, you can use algebra!
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,h_400,q_80,w_640.png)
Turning sentences into algebra
Turning sentences into algebra
- You can turn sentences into algebra.
,h_400,q_80,w_640.png)
,h_400,q_80,w_640.png)
Solving algebra
Solving algebra
- To solve something in algebra means to find the number that should go instead of the letter to make the equation work.
- In this example, n = 13.
Missing Number Problems
Missing Number Problems
You can use missing number problems to find missing numbers in examples in real life.


Example
Example
- I am making a cake.
- The weight of the cupcake case is 12 g.
- Each cupcake case is filled with different amounts of cake mixture (c).
,h_400,q_80,w_640.png)
,h_400,q_80,w_640.png)
The missing number problem
The missing number problem
- The expression to solve this problem is 12 + c = w.
- 12 is the weight of the cupcake case.
- c is the weight of the cake mixture.
- w is the weight of the cupcake.
,h_400,q_80,w_640.png)
,h_400,q_80,w_640.png)
Substitution
Substitution
- You can work out the missing values in the table by substituting the values into you know into 12 + c = w.
,h_400,q_80,w_640.png)
,h_400,q_80,w_640.png)
Weight of mixture = 324 g
Weight of mixture = 324 g
- 12 + c = w
- 12 + 324 = w
- w = 336 g
,h_400,q_80,w_640.png)
,h_400,q_80,w_640.png)
Weight of cupcake = 356 g
Weight of cupcake = 356 g
- 12 + c = w
- 12 + c = 356
- c = 356 − 12
- c = 344 g
1Year 5 - Number
1.1Number & Place Value
1.2Addition & Subtraction
1.3Multiplication & Division
2Year 5 - Measurement
2.2Perimeter & Area
2.3Time
3Year 5 - Geometry
3.1Properties of 3D Shapes
3.2Properties of 2D Shapes
3.4Position & Direction
4Year 5 - Statistics
5Year 6 - Number
5.1Number & Place Value
5.2Multiplication & Division
5.3Mental Maths
5.4Order of Operations
5.5Problem Solving
5.6Fractions & Decimals
6Year 6 - Ratio & Proportion
6.2Percentages
6.3Scale
7Year 6 - Algebra
7.2Missing Number Problems
8Year 6 - Measurement
8.1Problem Solving
8.2Unit Conversion
8.3Perimeter, Area & Volume
8.4Angles
8.5Circles
8.6Coordinate Grids
9Year 6 - Statistics
9.1Displaying Data
9.2Averages
Jump to other topics
1Year 5 - Number
1.1Number & Place Value
1.2Addition & Subtraction
1.3Multiplication & Division
2Year 5 - Measurement
2.2Perimeter & Area
2.3Time
3Year 5 - Geometry
3.1Properties of 3D Shapes
3.2Properties of 2D Shapes
3.4Position & Direction
4Year 5 - Statistics
5Year 6 - Number
5.1Number & Place Value
5.2Multiplication & Division
5.3Mental Maths
5.4Order of Operations
5.5Problem Solving
5.6Fractions & Decimals
6Year 6 - Ratio & Proportion
6.2Percentages
6.3Scale
7Year 6 - Algebra
7.2Missing Number Problems
8Year 6 - Measurement
8.1Problem Solving
8.2Unit Conversion
8.3Perimeter, Area & Volume
8.4Angles
8.5Circles
8.6Coordinate Grids
9Year 6 - Statistics
9.1Displaying Data
9.2Averages
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