Go through the Math in Focus Grade 3 Workbook Answer Key Chapter 2 Practice 1 Mental Addition to finish your assignments.

## Math in Focus Grade 3 Chapter 2 Practice 1 Answer Key Mental Subtraction

**Add mentally. First, add the tens. Then, add the ones.**

Example

Question 1.

24 + 55 = ?

24 + 50 = ___

___ + ___ = ___

So, 24 + 55 = ____

Answer:

24 + 50 = 74

74 + 5 = 79

So, 24 + 55 = 79

Question 2.

22 + 64 = ?

20 + 64 = ___

___ + ___ = ____

So, 22 + 64 = ___

Answer:

20 + 64 = 84

84 + 2 = 86

So, 22 + 64 = 86

**Add mentally. Use number bonds to help you.**

Example

Question 3.

37 + 45 = ?

37 + 50 = __

___ – ___ = ___

So, 37 + 45 = ___

Answer:

37 + 50 = 87

87 – 5 = 82

So, 37 + 45 = 82

Question 4.

46 + 34 = ?

46 + 40 = ___

__ – __ = ___

So 46 + 34 = ___

Answer:

46 + 40 = 86

86 – 6 = 80

So 46 + 34 = 80

**Add mentally. Use number bonds to help you.**

Question 5.

41 + 43 = ___

Answer:

41 + 43

40 + 40 = 80

80 + 1 + 3 = 84

So, 41 + 43 = 84

Question 6.

31 + 64 = ___

Answer:

31 + 64

30 + 60 = 90

90 + 1 + 5 = 95

So, 31 + 64 = 95

Question 7.

15 + 47 = ___

Answer:

15 + 47

15 + 50 = 65

65 – 3 = 62

So, 15 + 47 = 62

Question 8.

46 + 48 = ___

Answer:

46 + 48

50 + 50 = 100

100 – 4 -2 = 94

So, 46 + 48 = 94