Fact Families

Presentation By: Meagan Warner

September 13, 2012

Overview Today I will teach you how to master fact

families I will:

Teach you the general guidelines for finding a fact family

Show you hints and shortcuts for finding fact families

Give you several examples so that you can practice

Basics In fact families, there are 3 numbers

organized in 4 different ways In a family, people are related. In a fact

family, numbers are related.

How to find a fact family In finding a fact family, there will always be

three numbers involved. For example,

If the 3 numbers you are asked to find a fact family for are 2, 6, and 8, then 2, 6, and 8 will be the only numbers in your fact family.

There will also always be 2 sums and 2 differences.

Tricks for fact families In a fact family, the biggest number will

always be both of the answers to your sums.

Example For example,

If 2, 5, and 7 are the numbers in your fact family, then 7 will be both answers to the sums. ___ + ___ = 7 ___ + ___ = 7

Practice If 3, 6, and 9 are the numbers in your fact

family, where do the 9’s go in your sums? ___ + ___ = 9 ___ + ___ = 9

Sums in Fact Families To find your first sum, find the two smallest

numbers and add them together. Remember, your biggest number will be what the

sum is set equal to. To find the numbers that go in your second

sum, reverse the numbers you used in your first sum.

For example, in the 3, 6, and 9 fact family 3 + 6 = 9 So… 6 + 3 = 9

Practice If the numbers in a fact family are 4, 5, and 9,

find the sums. 4 + 5 = 9 5 + 4 = 9

Tricks for fact families The biggest number will

also always be the first number for your differences.

Example For example,

If 2, 5, and 7 are the numbers in your fact family, then 7 will be the first digit in your differences. 7 - ___ = ___ 7 - ___ = ___

Practice If 3, 6, and 9 are the numbers in your fact

family, where do the 9’s go in your differences?

9 - = 9 - =

Differences In fact family differences, which ever number

that was the answer in the first difference will be the number that you subtract from the big number.

For example, In the 3, 6, and 9 fact family

9 – 6 = 3 So… 9 – 3 = 6

Completing fact families Find the fact family for 1, 5, and 6. 1 + 5 = 6 5 + 1 = 6 6 – 1 = 5 6 – 5 = 1

Completing fact families Find the fact family for 2, 5, and 7. 2 + 5 = 7 5 + 2 = 7 7 – 2 = 5 7 – 5 = 2

Completing fact families Find the fact family for 4, 5, and 9. 4 + 5 = 9 5 + 4 = 9 9 – 4 = 5 9 – 5 = 4

Conclusion

Now you are a master of fact families. Use what you have learned today when

answering fact family questions. And don’t forget

There will only be 3 numbers in a fact family The biggest number will always be the answer to

both of your sums The biggest number will also always be the first

number in both of your differences

Resources http://www.bellaonline.com/articles/art57615.

asp http://mathcentral.uregina.ca/QQ/database/Q

Q.09.03/keisha1.html