分数的操作顺序讲解.ppt

Mathematics is a type of language and it also has a specific order. Ex. 3 + 5 X 2 What do we do first? Add or multiply? If we add first: 3 + 5 X 2 8 X 2 16 If we multiply first: 3 + 5 X 2 10 3 + 13 Uh Oh! Which one is the correct answer? Help! Oh no! Part 1 Using the Order of Operations 3 + 5 X 2 What do we do first? BEDMAS 10 3 + 13 Multiply first Then add To simplify an expression means to replace the expression with the simplest name for its value. Example 1: Simplify 4 + 15 ÷ 3 4 + 15 ÷ 3 BEDMAS 5 4 + 9 Divide first Then add Now you try! 1) 2 + 5 X 3 2) 12 ÷ 3 - 1 3) 10 – 1 7 . Simplify each expression. When operations have the same rank in the order of operations, do them from left to right. Example 2 Simplify 3 5 – 8 ÷ 4 + 6 . BEDMAS 3 5 – 8 ÷ 4 + 6 . multiply divide from left to right 15 2 - + 6 13 + 6 19 add and subtract from left to right Try This! Simplify each expression 4) 4 – 1 2 + 6 ÷ 3 . 5) 5 + 6 4 ÷ 3 - 1 . Solving problems with fractions work exactly the same way BEDMAS Practice Expression #1 Common Denominator Common Denominator Subtract in Parentheses Exponent Multiply Addition Addition and Simplify Practice Expression #2 Common Denominator Addition Addition in Parentheses Exponent Multiply Subtraction Simplify Think about what this means… * * * * * * * * * * * * * *