Instructions
Let's learn two super cool rules for addition! These rules are like secret math tricks that make adding easier. Follow the instructions for each section. Good luck!
Part 1: The Flip-Flop Rule!
The Flip-Flop Rule says you can add numbers in any order, and the answer will be the same. It's like putting on your socks—it doesn't matter if you do the left or right one first!
Example: 4 + 5 = 9 is the same as 5 + 4 = 9
1. Fill in the blank to complete the flip-flop equation.
- A) 7 + 8 = 8 + ___
- B) 12 + 5 = ___ + 12
- C) ___ + 10 = 10 + 9
- D) 25 + 15 = 15 + ___
2. Solve both equations to see that the answers are the same!
6 + 11 = ___
11 + 6 = ___
14 + 3 = ___
3 + 14 = ___
Part 2: The Buddy Rule!
The Buddy Rule says that when you add three or more numbers, you can group them with "buddies" in different ways. Add the buddies in the parentheses ( ) first, and the final answer will always be the same!
Example: (2 + 3) + 4 --> 5 + 4 = 9
is the same as 2 + (3 + 4) --> 2 + 7 = 9
3. Fill in the missing "buddy" number.
- A) (5 + 4) + 2 = 5 + (___ + 2)
- B) 10 + (8 + 1) = (10 + ___) + 1
4. Solve both equations. Remember to do the part in ( ) first!
(4 + 6) + 5 = ___
4 + (6 + 5) = ___
(9 + 2) + 3 = ___
9 + (2 + 3) = ___
Part 3: What's The Rule?
Look at each pair of equations below. Is it showing the Flip-Flop Rule or the Buddy Rule? Circle your answer.
A) 13 + 7 = 7 + 13 Flip-Flop Rule / Buddy Rule
B) (8 + 2) + 9 = 8 + (2 + 9) Flip-Flop Rule / Buddy Rule
C) 20 + (10 + 5) = (20 + 10) + 5 Flip-Flop Rule / Buddy Rule
D) 50 + 40 = 40 + 50 Flip-Flop Rule / Buddy Rule
Answer Key
Part 1: The Flip-Flop Rule!
1. Fill in the blank:
- A) 7 + 8 = 8 + 7
- B) 12 + 5 = 5 + 12
- C) 7 + 10 = 10 + 7 (Note: The sum is 17, so the missing number is 7)
- D) 25 + 15 = 15 + 25
2. Solve both equations:
6 + 11 = 17
11 + 6 = 17
14 + 3 = 17
3 + 14 = 17
Part 2: The Buddy Rule!
3. Fill in the missing "buddy":
- A) (5 + 4) + 2 = 5 + (4 + 2)
- B) 10 + (8 + 1) = (10 + 8) + 1
4. Solve both equations:
(4 + 6) + 5 = 15
4 + (6 + 5) = 15
(9 + 2) + 3 = 14
9 + (2 + 3) = 14
Part 3: What's The Rule?
A) Flip-Flop Rule
B) Buddy Rule
C) Buddy Rule
D) Flip-Flop Rule