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Numeracy

10 Digits Make all Numbers: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9

Decimal System: Ten is a two-digit number, 10. The decimal system is based on 10 in a digit parking place system where each spot is a multiple of 10, with the decimal POINT separating whole numbers on the left from fractions of wholes on the right.

Each digit represents an amount. Digits are less than 10.

Zero 0 represents nothing.

Addition, Plus, + Combine

0 = nothing

1 = 0 + 1

1 = 1 + 0

2 = 0 + 2

2 = 1 + 1

2 = 2 + 0

3 = 0 + 3

3 = 1 + 1 + 1

3 = 1 + 2

3 = 2 + 1

3 = 3 + 0

4 = 0 + 4

4 = 1 + 1 + 1 + 1

4 = 1 + 3

4 = 2 + 2

4 = 3 + 1

4 = 4 + 0

5 = 0 + 5

5 = 1 + 1 + 1 + 1 + 1

5 = 1 + 4

5 = 2 + 3

5 = 3 + 2

5 = 4 + 1

5 = 5 + 0

6 = 0 + 6

6 = 1 + 1 + 1 +

1 + 1 + 1

6 = 1 + 5

6 = 2 + 4

6 = 3 + 3

6 = 4 + 2

6 = 5 + 1

6 = 6 + 0

7 = 0 + 7

7 = 1 + 1 + 1

+ 1 + 1 + 1 + 1

7 = 1 + 6

7 = 2 + 5

7 = 3 + 4

7 = 4 + 3

7 = 5 + 2

7 = 6 + 1

7 = 7 + 0

8 = 0 + 8

8 = 1 + 1 + 1 + 1 +

1 + 1 + 1 + 1 +

8 = 1 + 7

8 = 2 + 6

8 = 3 + 5

8 = 4 + 4

8 = 5 + 3

8 = 6 + 2

8 = 7 + 1

8 = 8 + 0

9 = 0 + 9

9 = 1 + 1 + 1

1 + 1 + 1

1 + 1 + 1

9 = 1 + 8

9 = 2 + 7

9 = 3 + 6

9 = 4 + 5

9 = 5 + 4

9 = 6 + 3

9 = 7 + 2

9 = 8 + 1

9 = 9 + 0

MAKING TEN

10 = 0 + 10

10 = 1 + 9

10 = 2 + 8

10 = 3 + 7

10 = 4 + 6

10 = 5 + 5

10 = 6 + 4

10 = 7 + 3

10 = 8 + 2

10 = 9 + 1

10 = 10 + 0

TEENS NUMBERS

TEN + A DIGIT

10 = 10 + 0

11 = 10 + 1

12 = 10 + 2

13 = 10 + 3

14 = 10 + 4

15 = 10 + 5

16 = 10 + 6

17 = 10 + 7

18 = 10 + 8

19 = 10 + 9

Ten 10

Eleven

one + ten = 11

Twelve

two + ten = 12

Thirteen

three + ten = 13

Subtraction, Take Away, Remove

0 = nothing

1 - 0 = 1

1 - 1 = 0

2 - 0 = 2

2 - 1 = 1

2 - 2 = 0

3 - 0 = 3

3 - 1 - 1 - 1 = 0

3 - 1 = 2

3 - 2 = 1

3 - 3 = 0

4 - 0 = 4

4 - 1 - 1 - 1 - 1 = 0

4 - 1 = 3

4 - 2 = 2

4 - 3 = 1

4 - 4 = 0

5 - 0 = 5

5 - 1 - 1 - 1- 1-1 = 0

5 - 1 = 4

5 - 2 = 3

5 - 3 = 2

5 - 4 = 1

5 - 5 = 0

6 - 0 = 6

6 - 1 - 1 - 1 -

1 - 1 - 1 = 0

6 - 1 = 5

6 - 2 = 4

6 - 3 = 3

6 - 4 = 2

6 - 5 = 1

6 - 6 = 0

7 - 0 = 7

7 - 1 - 1 - 1

- 1 - 1 - 1 - 1 = 0

7 - 1 = 6

7 - 2 = 5

7 - 3 = 4

7 - 4 = 3

7 - 5 = 2

7 - 6 = 1

7 - 7 = 0

8 - 0 + 8

8 - 1 - 1 - 1 - 1 -

1 - 1 - 1 - 1 = 0

8 - 1 = 7

8 - 2 = 6

8 - 3 = 5

8 - 4 = 4

8 - 5 = 3

8 - 6 = 2

8 - 7 = 1

8 - 8 = 0

9 - 0 = 9

9 - 1 - 1 - 1

1 - 1 - 1

1 - 1 - 1 = 0

9 - 1 = 8

9 - 2 = 7

9 - 3 = 6

9 - 4 = 5

9 - 5 = 4

9 - 6 = 3

9 - 7 = 2

9 - 8 = 1

9 - 9 = 0

MAKING TEN

10 - 0 = 10

10 - 1 = 9

10 - 2 = 8

10 - 3 = 7

10 - 4 = 6

10 - 5 = 5

10 - 6 = 4

10 - 7 = 3

10 - 8 = 2

10 - 9 = 1

10 - 10 = 0

10 - 0 = 10

11 - 1 = 10

12 - 2 = 10

13 - 3 = 10

14 - 4 = 10

15 - 5 = 10

16 - 6 = 10

17 - 7 = 10

18 - 8 = 10

19 - 9 = 10

20 - 10 = 10

9 + 1 = 10

9 + 2 = 10 + 2 - 1

9 + 3 = 10 + 3 - 1

9 + 4 = 10 + 4 - 1

9 + 5 = 10 + 5 - 1

9 + 6 = 10 + 6 - 1

9 + 7 = 10 + 7 - 1

9 + 8 = 10 + 8 - 1

9 + 9 = 10 + 9 - 1

9 + 10 = 19

9 + 11 = 10 + 9 + 1 = 20

Double Numbers

0 + 0 = 0

1 + 1 = 2

2 + 2 = 4

3 + 3 = 6

4 + 4 = 8

5 + 5 = 10

6 + 6 = 12

7 + 7 = 14

8 + 8 = 16

9 + 9 = 18

10 + 10 = 20

11 + 11 = 22

12 + 12 = 24

Multiplication (Adding the same thing multiple times) & Division (Subtracting the same thing multiple times).

Practice facts many ways:

Add - Subtract:

4 + 5 = 9

4x + 5x = 9x

4xy + 5xy = 9xy

4xyz + 5xyz = 9xyz

40 + 50 = 90

400 + 500 = 900

4,000 + 5,000 = 9,000

4/10 + 5/10 = 9/10

.4 + .5 = .9

4 million + 5 million = 9 M

9 - 5 = 4

.9 - .4 = .5

9/10 - 5/10 = 4/10

9M - 4M = 5M

9¢ - 5¢ = 4¢

$9 - $4 = $5

9/1000 - 5/1000 = 4/1000

9/k - 4/k = 5/k

-5 - 4 = -5

Multiply - Divide:

7 × 9 = 63

9 × 7 = 63

.9 × .7 = .63

63 ÷ 7 = 9

63 ÷ 9 = 7

63x ÷ 7x = 9x

63x ÷ 9x = 7x

63/7 = 9

63/9 = 7

63/10 ÷ 9/10 = 7/10

63/10 ÷ 7/10 = 9/10

63,000 ÷ 9,000 = 7,000

63,000 ÷ 7,000 = 9,000

630 ÷ 90 = 70

630 ÷ 70 = 90

6,300 ÷ 900 = 700

6,300 ÷ 700 = 900

63M ÷ 9M = 7M

63GB ÷ 9GB = 7GB

Multiply - Divide Practice

Example:

3 + 3 + 3 + 3 = 12

3 × 4 = 12

4 × 3 = 12

3(4)= 12

4(3)= 12

3*4 = 12

4*3 = 12

4 • 3 = 12

3 • 4 = 12

Example:

3a + 3a + 3a + 3a = 12a

3a × 4 = 12a

4a × 3 = 12a

3(4a)= 12a

4a(3)= 12a

3a*4 = 12a

4*3a = 12a

4a • 3 = 12a

3a • 4 = 12a

Example:

3/10 + 3/10 + 3/10 + 3/10 = 12/10

3/10 × 4 = 12/10

4/10 × 3 = 12/10

3/10(4)= 12/10

4/10(3)= 12/10

3/10*4 = 12/10

4*3/10 = 12/20

.4 • .3 = .12

.3 • .4 = .12

Multiplication: Short vs. Long

Multiply two digits from R to L, and add the leftovers, then write the product below the line in the column of the multiplicand.

Multiply two digits from R to L and write the product so it ends in the parking spot of the multiplicand. Sum each column.

Long Division

Divide the dividend by the divisor, from L to R. Write the quotient on top in the same column as the digit in the dividend.

Minus - Give Ten, Make 10