• 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

• 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

Doubles + 1

• 1 + 2 = 3
• 2 + 3 = 5
• 3 + 4 = 7
• 4 + 5 = 9
• 5 + 6 = 11
• 6 + 7 = 13
• 7 + 8 = 15
• 8 + 9 = 17
• 9 + 10 = 19
• 10 + 11 = 21

Two addition and two subtraction problems.

Same three numbers appear in different places.

In addition problems, the largest number appears last.

Example: 7, 2, and 9

• 7 + 2 = 9
• 2 + 7 = 9

In subtraction problems, the largest number appears first.

• 9 - 2 = 7
• 9 - 7 = 2

To know which symbol (<  >) to use, put two dots near the larger number and one dot near the smaller number.  Then connect the dots.

Numbers that are the same are equal to each other.

749,381

Standard Form

Expanded Form

700,000 + 40,000 + 9,000 + 300 + 80 + 1

Word Form

Seven hundred forty-nine thousand, three hundred eighty-one

The value of a number depends on location.  If you have 13,020 and need to know the value of the 3, look for its location.  The 3 is in the thousand’s place.  The value of the 3 is three thousand.

Example: What is the value of 3?  

13,020

Once the number is identified, fill every place to the right with zeros.

The value of 3 is 3,000

Boss Hog 9 takes 1 from the other addend making 10.  Add what is left to the 10 to find the sum.

Example: 9 + 6 = ?

9 + 1 = 10

6 - 1 = 5

10 + 5 = 15