Beach Day Fact Families: Add and Subtract Within 20
0 / 12Beach Day Fact Families: Add and Subtract Within 20
Use fact families and easier problems to add and subtract.
Seashell fact families
Each fact family uses the same three numbers. Write the missing numbers.
1.
Noah's seashell fact family uses 6, 9, and 15. Finish the four facts.
6 + 9 =
9 + 6 =
15 − 6 =
15 − 9 =
2.
Use the addition fact to solve the subtraction fact.
7 + = 12
So 12 − 7 =
3.
Which fact is NOT in the fact family for 4, 9, and 13?
4.
There are 14 kids at the beach. 6 kids are swimming. The rest are building sandcastles. How many kids are building sandcastles? Think: 6 + ? = 14.
14 − 6 = kids
Make an easier problem
Move some to make a 10. Then the problem is easier to add.
5.
Mia has 9 pails and 5 shovels. Move 1 to the 9 to make 10.
9 + 5 is the same as 10 +
So 9 + 5 =
6.
Omar sees 8 crabs and 7 starfish. Move 2 to the 8 to make 10.
8 + 7 is the same as 10 +
So 8 + 7 =
7.
Match each problem to the easier problem with the same total.
8.
Kai wants to solve 6 + 8. Which easier problem has the same total?
Snack bar quick facts
Solve each fact. Try to answer the facts within 10 quickly.
9.
Each beach towel shows a fact. Sort each fact by its answer.
10.
Quick facts within 10.
5 + 4 =
10 − 3 =
6 + 2 =
9 − 5 =
11.
Ella brings 12 juice boxes to the beach. Her family drinks 4 of them. How many juice boxes are left?
12.
Ana says, "I know 9 + 8 = 17, so I know 17 − 8." What is 17 − 8? Tell how the addition fact helps.