Step-by-step Maths Level 1: Parts and wholes
Part of the Step-by-step Maths Level 1 number bonds to 5 chapter. Chapter overview · whole chapter on one page
Parts and wholes
A number can be made from two parts. The whole number is at the top. The two parts are below.
If you know the whole and one part, you can find the other part.
Key ideas
- The whole is at the top.
- The two parts are below it.
- Parts add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 4.5 and 4
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 4 = 1
- Write the missing part. 1
Check. Put the two parts back together: 4 and 1 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 1.5 and 1
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 1 = 4
- Write the missing part. 4
Check. Put the two parts back together: 1 and 4 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 3.5 and 3
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 3 = 2
- Write the missing part. 2
Check. Put the two parts back together: 3 and 2 make 5.
Watch out. The two parts always add up to the whole.
Watch out
Watch out. Do not add the known part to the whole. Take the known part away from 5.
Exam tip
Grown-up tip. Use five cubes or buttons. Split them into two piles, then ask: “How many in each pile?” Find as many ways as you can.
Exercise 4A Parts and wholes
Non-calculatorMethod. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 4.5 and 4
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 4 = 1
- Write the missing part. 1
Check. Put the two parts back together: 4 and 1 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 4.5 and 4
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 4 = 1
- Write the missing part. 1
Check. Put the two parts back together: 4 and 1 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 1.5 and 1
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 1 = 4
- Write the missing part. 4
Check. Put the two parts back together: 1 and 4 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 1.5 and 1
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 1 = 4
- Write the missing part. 4
Check. Put the two parts back together: 1 and 4 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 2.5 and 2
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 2 = 3
- Write the missing part. 3
Check. Put the two parts back together: 2 and 3 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 0.5 and 0
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 0 = 5
- Write the missing part. 5
Check. Put the two parts back together: 0 and 5 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 1.5 and 1
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 1 = 4
- Write the missing part. 4
Check. Put the two parts back together: 1 and 4 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 1.5 and 1
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 1 = 4
- Write the missing part. 4
Check. Put the two parts back together: 1 and 4 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 1.5 and 1
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 1 = 4
- Write the missing part. 4
Check. Put the two parts back together: 1 and 4 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 4.5 and 4
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 4 = 1
- Write the missing part. 1
Check. Put the two parts back together: 4 and 1 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 2.5 and 2
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 2 = 3
- Write the missing part. 3
Check. Put the two parts back together: 2 and 3 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 0.5 and 0
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 0 = 5
- Write the missing part. 5
Check. Put the two parts back together: 0 and 5 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 3.5 and 3
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 3 = 2
- Write the missing part. 2
Check. Put the two parts back together: 3 and 2 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 0.5 and 0
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 0 = 5
- Write the missing part. 5
Check. Put the two parts back together: 0 and 5 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 3.5 and 3
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 3 = 2
- Write the missing part. 2
Check. Put the two parts back together: 3 and 2 make 5.
Watch out. The two parts always add up to the whole.
Method. Find the missing part. Ask what goes with the known part to make the whole.
- Look at the whole and the part you know. The whole is 5 and the known part is 0.5 and 0
- Count on from the known part to the whole. Or take the known part away from the whole.5 - 0 = 5
- Write the missing part. 5
Check. Put the two parts back together: 0 and 5 make 5.
Watch out. The two parts always add up to the whole.