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Adding and subtracting up to 10
Comparing numbers up to 10
Adding and subtracting up to 20
Addition and Subtraction within 20
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Practice
Adding and Subtracting Numbers up to 20
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Adding and Subtracting Numbers up to 20 : Difficult Problems with Solutions
Problem 1
14 - 5 =
Solution:
14 - 5 = 9
Problem 2
8 + 7 =
Solution:
8 + 7 = 15
Problem 3
8 + 3 + 2 =
Solution:
8 + 3 + 2 = 13
Problem 4
6 + 6 =
Solution:
6 + 6 = 12
Problem 5
9 + 8 =
Solution:
9 + 8 = 17
Problem 6
13 - 7 =
Solution:
13 - 7 = 6
Problem 7
19 - 14 =
Solution:
19 - 14 = 5
Problem 8
9 + 7 =
Solution:
9 + 7 = 16
Problem 9
Solution:
15 - 12 = 3
Therefore, 15 - 3 = 12
Answer: 3
Problem 10
Solution:
16 - 7 = 9
9 + 7 = 16
Problem 11
Solution:
19 - 7 = 11
Problem 12
Solution:
5 + 7 = 12
Therefore, 12 - 7 = 5
Problem 13
+ 8 = 17
Solution:
9 + 8 = 17 because 17 - 8 = 9
Problem 14
- 10 = 10
Solution:
20 - 10 = 10
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