91热爆

Fact families

Watch this slideshow all about creating a fact family.

Image gallerySkip image gallerySlide 1 of 6, 15 red counters and three yellow counters with number cards 18, 3 and 15, Fact families are made from three numbers. The numbers in this fact family are 18, 3 and 15. 18 is our whole, 15 represents the red counters and 3 represents the yellow counters.
Back to top

Part whole models

A part whole model can be helpful when working out simple calculations. They are a visual representation of writing out number sentences and can help solve missing fact family numbers.

Image gallerySkip image gallerySlide 1 of 5, 8 red counters and 7 yellow counters. Additions and subtractions 8 + 7 =15, 7 + 8 = 15, 15 - 7 = 8, 15 - 8 =7, Here is a different fact family. In this case, there are 8 red counters and 7 yellow counters, so the three numbers in this fact family are 8, 7 and 15.
Back to top

Example 1

Have a look at this part whole model.

The top circle contains the number twenty, the bottom left circle contains the number twelve and the bottom right circle contains the number eight.

The model shows that the numbers 20, 12 and 8 are part of a fact family.

The number 20 is made of two parts, 12 and 8.

The diagram can help you work out possible number sentences in the fact family.

12 + 8 = 20

8 + 12 = 20

20 - 8 = 12

20 - 12 = 8

Back to top

Activity

Back to top

NEW! Play Guardians: Defenders of Mathematica - the winter update. game

It's Mathematica as you鈥檝e never seen it before, with all-new festive backgrounds and costumes. Available for a limited time only. Use your maths skills to save the day before it's too late!

NEW! Play Guardians: Defenders of Mathematica - the winter update
Back to top

More on Adding and subtracting

Find out more by working through a topic