Strategies for solving 3 digit addition problems Traditional

Strategies for solving 3 digit addition problems.

Traditional Algorithm Write the problem up and down, then add the columns, starting with the ones, to solve. 1 547 + 262 = 547 + 262 8 10 9 809 can’t have 2 digits in a place, so the 1 in the tens place goes to be added with the hundreds since it is really 10 tens, which is 100.

Using a Number Line Strategy Start with one of the numbers (usually the larger number), then skip count by ones, tens, then hundreds on an open number line to add the next number. 547 + 262 = count on by ones 547 549 count by tens count by 100’s 609 809

Counting On Strategy (my favorite) Similar to the open number line, however this uses lines to represent the ones, tens, and hundreds as they are being added on. Again, start with one of the numbers (usually the larger number), then place horizontal lines for the amount of ones, then tens, then hundreds. Once that is done, skip count appropriately filling in the lines. 547 + 262 = 547 by ones 547 548 549 559 by ones 547 549 by tens by hundreds 569 579 589 599 609 709 by tens 609 809 by hundreds 809

Base Ten Models Strategy Use models to add. Draw out the hundreds, tens and ones of a number (usually the larger number). Then draw out the hundreds, tens, and ones of the other number. Then add the ones, then tens, then hundreds. This strategy might need regrouping if a place is higher than 10. 547 + 262 = 9 ones = 9 10 tens get traded for a 100 so now 0 tens 8 hundreds = 809

Expanded Form Strategy Break each number down into its values then add the results. 547 + 262 = 500 + 40 + 7 + 200 + 60 + 2 800 + 100 + 9 = 909

Place Value Strategy Break each number down into its values adding the values together 547 + 262 = 500 + 200 = 700 40 + 60 = 100 7+2=9 700 + 100 + 9 = 809

Other Strategies ** There are other strategies your children might like to use, and that is fine as long as they are getting the correct answer. The strategies in this presentation are the strategies I will be teaching in class.