Add one ,two and three Digit Numbers.

Standard: 3.NBT.A.2

Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction.

Learning Outcomes

Students will understand how to add a 1-digit number and a 2-digit number together (e.g., 7 + 25 = 32) and recognize when regrouping is needed.
Students will fluently add a 2-digit number to a 3-digit number (e.g., 45 + 378 = 423) by aligning digits correctly and carrying over when necessary.
Students will successfully add two 3-digit numbers (e.g., 487 + 312 = 799), practicing regrouping in both the ones and tens places.
Students will be able to confidently apply addition to real-life scenarios and math problems involving sums of varying lengths.

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Definition Adding Numbers:

1-Digit Addition:

This is the simplest form of addition, where both numbers being added have only one digit. The sum typically results in a number between 0 and 18 (if both numbers are at most 9).
Example: 7 + 5 = 12.

2-Digit Addition:

In 2-digit addition, both numbers consist of two digits (a number in the tens place and a number in the ones place). When adding 2-digit numbers, the addition process may involve regrouping (carrying over) if the sum in the ones or tens place is greater than 9.
Example: 45 + 32 = 77.

3-Digit Addition:

3-digit addition involves adding numbers that have a hundred, tens, and one's place. Similar to 2-digit addition, this process may require regrouping if the sum in any place value exceeds 9.
Example: 378 + 456 = 834.

Example 1:

Adding a 1-digit number and a 2-digit number: 7 + 25.

Solution:

Align the numbers based on place value: 7+25.

Start with the one's place:
- 5 + 7 = 12. Write 2 in the one's place and carry over 1 to the tens place.
Add the tens place:
- 2 (from 25) + 1 (carry-over) = 3.
Final solution: 7 + 25 = 32.

Example 2:

Adding a 2-digit number and a 3-digit number: 45 + 378.

Solution:

Align the numbers by place value: 378+45.
Start with the one place:
- 8 + 5 = 13. Write 3 in the one's place and carry over 1 to the tens place.
Move to the tens place:
- 7 + 4 = 11, and add the carry-over 1: 11 + 1 = 12. Write 2 in the tens place and carry over 1 to the hundreds place.
Add the hundreds place:
- 3 (from 378) + 1 (carry-over) = 4.
Final Solution: 45 + 378 = 423.

Example 3:

Adding Two 2-digit Numbers: 56 + 73.

Solution:

Align the numbers by place value: 56+73.
Add the ones in place:
- 6 + 3 = 9.
Add the tens place:
- 5 + 7 = 12. Write 2 in the tens place and carry over 1 to the hundreds.
Final Answer: 56 + 73 = 129.

Example 4:

Adding a 1-digit number and a 3-digit number: 5 + 632.

Solution:

Align the numbers by place value: 632+5.
Start with the one's place:
- 2 + 5 = 7.
Since there are no digits in the tens or hundreds place of the second number, move directly to the next places:
- Tens place: 3 (from 632) remains as 3.
- Hundreds place: 6 (from 632) remains as 6.
Final Solution: 5 + 632 = 637.

Why it matters:

Adding multi-digit numbers is a fundamental math skill that helps in solving everyday problems, from calculating expenses to measuring quantities. Mastering addition improves problem-solving, logical thinking, and mental math abilities.

By practicing addition with 2-digit numbers, you'll be able to solve real-world problems quickly!

Let's practice and evaluate your work by multi-digit addition