Pre-Algebra Demystified

2. Round 563,218 to the nearest ten thousands.


3. Round 80,006 to the nearest 10.


4. Round 478,375 to the nearest hundred thousand.


5. Round 32,864,371 to the nearest million.

ANSWERS

1. 4,


2. 560,


3. 80,


4. 500,


5. 33,000,

Addition of Whole Numbers

In mathematics, addition, subtraction, multiplication, and division are called

operations. The numbers being added are calledaddends. The total is called

thesum.

3 addend

þ 4 addend

7 sum

To add two or more numbers, first write them in a column, and then add the

digits in the columns from right to left. If the sum of the digits in any column is

10 or more, write the ones digit and carry the tens digit to the next column and

add it to the numbers in that column.

EXAMPLE

Add 24þ 185 þ3,625þ9.

SOLUTION

12 carry row

24

185

3,

þ 9

3 ; 843

Math Note: To check addition, add from the bottom to the top.

4 CHAPTER 1 Whole Numbers