Mental Math Subtraction

Round 57 to the nearest ten

• 50

• 55

• 60

• 67

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.A.3

Round 82 to the nearest ten.

• 80

• 85

• 90

• 92

Tags

CCSS.3.NBT.A.1

CCSS.4.NBT.A.3

Do you need to regroup to subtract 72-47?

• Yes

• No

Tags

CCSS.2.NBT.B.5

Do you need to regroup 88-25?

• Yes

• No

When using our mental math strategy…

Pick the number to round in

43-27

• 43

• 27

When using our mental math strategy…

Pick the number to round.

73-56=

• 73

• 56

To make 57 a ten add

Tags

CCSS.1.NBT.C.4

CCSS.2.MD.B.6

To make 48 a ten add

Tags

CCSS.2.NBT.B.5

When subtracting

63-39 you should first add

• 63+1

• 39+1

• 39+10

• 63+7

Tags

CCSS.2.NBT.B.5

When subtracting

71-58 you should first add

• 71+58

• 71+9

• 58+2

• Don’t add

Tags

CCSS.7.NS.A.1C