Add Whole Numbers

Keisha has 231 trading cards. Her brother has 467 trading cards. How many trading cards do they have in all?

Strategy: Add to find how many cards in all.

Step 1: Write the addition problem in a column. Line up the addends by place value.

Step 2: Add the ones.

Step 3: Add the tens.

Step 4: Add the hundreds.

What is the sum of 524 + 197?

Strategy: Rewrite the addition problem in a column.

Then add from right to left.

Step 1: Add the ones.

4 ones + 7 ones = 11 ones

Regroup 11 ones as 1 ten and 1 one.

Step 2: Add the tens. Remember to include the one regrouped ten.

1 ten + 2 tens +9 tens = 12 tens

Regroup 12 tens as 1 hundred and 2 tens.

Step 3: Add the hundreds. Remember to include the 1 regrouped hundred.

1 hundred + 5 hundreds + 1 hundred = 7 hundreds

Solution: 524+197=721

What is 400+200?

Strategy: Use mental math.

Step 1: Which place value is being added?

Step 2: Mentally add.

400+200=600

What is 295+349?

Strategy: Add to one addend what you subtract from the other.

Step 1: Add 5 to 295 and subtract 5 from 349.

295+5=300

349-5= 344

Step 2: Add the new addends mentally.

300+344=644