Algebra I/Content/Introduction to Basic Algebra Ideas/Simple Operations

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Back to Table of Contents Algebra I

Vocabulary

Operation

Equals Sign

Adding

Subtracting

Multiplying

Dividing

Lesson

An ''operation" is a thing you do to numbers. You use signs like: +, -, *, or / for operations.

The Equals Sign is not an operation. You use the " = " sign for the Equals Sign. It is a special sign that you put between two things that are the same.

Adding

Adding is a way to put two numbers together. You use the " + " sign for the adding operation. If you have 5 apples and a friend has 6 apples, you and your friend have 11 apples. This is 5 + 6 = 11 using the signs of Math.

Order is not important when adding. 2 + 3 is the same as 3 + 2.

Subtracting

Subtracting is a way of taking a number out from an other number. It is the opposite of adding. You use the " - " sign for the subtracting operation. If you have 5 apples and give 3 to a friend, you then have 2 apples. This is 5 - 3 = 2 using the signs of Math.

Order is important when subtracting. 3 - 2 is not the same as 2 - 3.

Multiplying

Multiplying is a way of adding a number many times. You use the " × " sign for the multiplying operation. If you have 4 apple trees and every tree has 25 apples, you have 100 apples. This is 4 × 25 = 100 or 25 + 25 + 25 + 25 = 100 in the signs of Math. The first way is shorter and easier to use.

Multiplying 25 by 4 is the same as adding 25, 4 times or adding 4, 25 times.

Order is not important when multiplying. 2 × 3 is the same as 3 × 2.

Dividing

Dividing is the opposite of multiplying. You use the " / " sign for the dividing operation. If 3 friends take an equal part of a bag of 12 apples, every friend gets 4 apples. This is 12 / 3 = 4 in the signs of Math.

Order is important when dividing. 3 / 2 is not the same as 2 / 3.

Example Problems

3 + 4 = 7

5 - 3 = 2

6 × 2 = 12

13 + 14 = 27

21 - 9 = 12

8 × 3 = 24

14 / 2 = 7

Practice Games

Addition Game

Subtraction Game

Multiplication Game


Practice Problems

  • 75 / 5 =
  • 12 * 3 =
  • 18 + 5 =
  • 90 - 75 =
  • 7 + 6 =