NUMBER DOJO
  • Home
  • Kahoot!
  • By Grade Level/Belt Color
  • Premium Content
    • Elementary School Curriculum (2019)
    • Middle School Curriculum (2019)
    • High School Curriculum (2019)
  • Store
  • Mathing Bee
  • Freebies
  • Speed Puzzling

Level 4: AddWhole

8/13/2015

0 Comments

 
When asked to add a group of whole numbers, we must recognize and group together the place values of each number.

Let us try 129 + 198 + 321.  The solution is (1 + 1 + 3) hundreds, plus (2 + 9 + 2) tens, plus (9 + 8 + 1) ones.

This is simplified as 5 hundreds plus 13 tens plus 18 ones.  13 tens is equal to 1 hundred plus 3 tens.  18 ones is equal to 1 ten plus 8 ones.

The answer is 5 hundreds + 1 hundred, plus 3 tens + 1 ten, plus 8 ones.  6 hundreds plus 4 tens plus 8 ones is simply 648.

Let us try an example where each number has different lengths, such as 2413 + 22 + 917.

Working from right to left, we have (7 + 1 + 3) ones, or 12 ones.  We write the 2 and regroup the 1 with the tens.  Then we have (1 + 2 + 1) tens, plus the regrouped 1, = 5 tens.

We write the 5 to the left of the 2.  Then we have (9 + 4) hundreds, or 13 hundreds. 

We write the 3 to the left of the 5 and regroup the 1 with the thousands. 

We have 2 plus the regrouped 1, or 3 thousands, so we write the 3 on the left.  The answer is 3352.

0 Comments



Leave a Reply.

    Author

    I competed in Number sense in the early 1990s.  Now, I'm coaching the next generation of superstars.  Hopefully, this site will be helpful to you.

    Archives

    August 2015

    Categories

    All

    RSS Feed

Home
Kahoot!
Mathing Bee
Store
Speed Puzzling
Copyright © 2019 Number Dojo (TM), www.NumberDojo.com