Doubles and Near Doubles in Addition
Use facts you know to add numbers that are close
Doubles and Near Doubles in Addition
Use facts you know to add numbers that are close
Math - Grade 2-3
- 1
Solve the doubles fact: 4 + 4 = ____.
4 + 4 = 8 because doubling 4 means adding 4 two times. - 2
Use the double 5 + 5 to solve 5 + 6. What is the sum?
First find 5 + 5, then add 1 more.
5 + 6 = 11. Since 5 + 5 = 10, one more makes 11. - 3
Solve: 7 + 7 = ____.
7 + 7 = 14 because two groups of 7 make 14. - 4
Use a near double to solve 7 + 8. Explain your thinking.
Start with the double 7 + 7.
7 + 8 = 15. I know 7 + 7 = 14, and 8 is one more than 7, so the sum is 15. - 5
Which doubles fact can help you solve 6 + 7? Write the doubles fact and the answer to 6 + 7.
Use the smaller addend to make a double first.
The doubles fact 6 + 6 = 12 can help. Since 7 is one more than 6, 6 + 7 = 13. - 6
Solve: 9 + 9 = ____.
9 + 9 = 18 because doubling 9 gives 18. - 7
Maya has 8 stickers. Her friend has 9 stickers. Use a near double to find how many stickers they have in all.
Think about the double 8 + 8.
They have 17 stickers in all. I know 8 + 8 = 16, and one more sticker makes 17. - 8
Circle the near double addition fact: 3 + 3, 4 + 5, or 6 + 2. Then solve it.
The near double is 4 + 5 because the addends are only 1 apart. 4 + 5 = 9. - 9
There are 5 red apples and 5 green apples in a basket. How many apples are there in all?
There are 10 apples in all because 5 + 5 = 10. - 10
Use 10 + 10 to solve 10 + 11. What is the sum?
Double 10 first, then add 1.
10 + 11 = 21. Since 10 + 10 = 20, one more makes 21. - 11
Solve: 2 + 3 = ____. Tell which doubles fact helped you.
Use the double with the smaller number.
2 + 3 = 5. The doubles fact 2 + 2 = 4 helped because 3 is one more than 2. - 12
A number line shows a jump of 6 and another jump of 7. What addition sentence does it show, and what is the sum?
The addition sentence is 6 + 7 = 13. I can use 6 + 6 = 12 and add 1 more to get 13. - 13
Fill in the blanks: 8 + 8 = ____, so 8 + 9 = ____.
8 + 8 = 16, so 8 + 9 = 17 because 9 is one more than 8. - 14
Which sum is larger, 6 + 6 or 6 + 7? Explain how you know.
Compare a double to the near double that has one more.
6 + 7 is larger. It is one more than 6 + 6, so 6 + 7 = 13 and 6 + 6 = 12. - 15
Liam builds 9 blocks in one tower and 10 blocks in another tower. Use a near double to find the total number of blocks.
Start with the double 9 + 9.
Liam has 19 blocks in all. I know 9 + 9 = 18, and one more block makes 19.