Doubling 2, 4, and 8 Fact Sets Flashcards

This deck uses doubling to solve 4 and 8 facts. NOTICE in the answers that one side of an equation is cut in half and the other side is doubled.

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1
Q

4 x 3 =
double (2 x 3)

A

(2 x 3) + (2 x 3) = 12
OR
2 x 6 = 12
OR
6 + 6 = 12

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2
Q

4 x 4 =
double (2 x 4)

A

(2 x 4) + (2 x 4) = 16
OR
2 x 8 = 16
8 + 8 = 16

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3
Q

4 x 6 =
double (2 x 6)

A

(2 x 6) + (2 x 6) = 24
OR
2 x 12 = 24
OR
8 x 3 = 24

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4
Q

4 x 8 =
double (2 x 8)

A

(2 x 8) + (2 x 8) = 32
OR
2 x 16 = 32
OR
8 x 4 = 32

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5
Q

4 x 9 =
double (2 x 9)

A

(2 x 9) + (2 x 9) = 36
OR
2 x 18 = 36
OR
18 + 18 = 36

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6
Q

4 x 10 =
double (2 x 10)

A

(2 x 9) + (2 x 9) = 40
OR
2 x 20 = 40
OR
8 x 5 = 40

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7
Q

4 x 11 =
double (2 x 11)

A

(2 x 11) + (2 x 11) = 44
OR
2 x 22 = 44
OR
22 + 22 = 44

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8
Q

4 x 12 =
double (2 x 12)

A

(2 x 12) + (2 x 12) = 48
OR
2 x 24 = 48
OR
8 x 6 = 48

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9
Q

8 x 2 =
double (4 x 2)

A

(4 x 2) + (4 x 2) = 16
OR
4 x 4 = 16
OR
8 + 8 = 16

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10
Q

8 x 3 =
double (4 x 3)

A

(4 x 3) + (4 x 3) = 24
OR
4 x 6 = 24
OR
12 + 12 = 24

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11
Q

8 x 4 =
double (4 x 4)

A

(4 x 4) + (4 x 4) = 32
OR
8 x 8 = 32
OR
16 x 2 = 32

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12
Q

8 x 5 =
double (4 x 5)

A

(4 x 5) + (4 x 5) = 40
OR
4 x 10 = 40
OR
20 + 20 = 40

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13
Q

8 x 6 =
double (4 x 6)

A

(4 x 6) + (4 x 6) = 48
OR
4 x 12 = 48
OR
16 x 3 = 48

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14
Q

4 x 2 =
double (2 x 2)

A

(2 x 2) + (2 x 2) = 8
OR
2 x 4 = 8
OR
4 + 4

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15
Q

4 x 1 =
double (2 x 1)

A

(2 x 1) + (2 x 1) = 4
OR
2 x 2 = 4
OR
2 + 2

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16
Q

8 x 1 =
double (4 x 1)

A

(4 x 1) + (4 x 1) = 8
OR
4 x 2 = 8
OR
4 + 4 = 8

17
Q

4 x 5 =
double (2 x 5)

A

(2 x 5) + (2 x 5) = 20
OR
2 x 10 = 20
OR
10 + 10 = 20

18
Q

4 x 7 =
double (2 x 7)

A

(2 x 7) + (2 x 7) = 28
OR
2 x 14 = 28
OR
14 + 14 = 28

19
Q

8 x 7 =
double (4 x 7)

A

(4 x 7) + (4 x 7) = 56
OR
4 x 14 = 56
OR
28 + 28 = 56

20
Q

8 x 8 =
double (4 x 8)

A

(4 x 8) + (4 x 8) = 64
OR
8 x 8 = 64
OR
4 x 16 = 64

21
Q

8 x 9 =
double (4 x 9)

A

(4 x 9) + (4 x 9) = 72
OR
4 x 18 = 72
OR
36 + 36 = 72

22
Q

8 x 10 = 80
double (4 x 10 = 40)

A

(4 x 10) + (4 x 10) = 80
OR
4 x 20 = 80
OR
16 x 5 = 80