Order of Operations. Mathematics 1st E.S.O.
Teacher: Miguel Ángel Hernández Lorenzo.
ORDER OF OPERATIONS
Example: Mr. Sanchez gave his class the problem 43×5 . Simone got the answer 35, but Joey got 19. Who is right? Explain your answer. Solution: Simone did the addition first: 43×5=7×5=35 . Joey did the multiplication first: 43×5=415=19 . Joey is right, because multiplication should be done before addition.
There is a set of rules to make sure everyone gets the same answer for the same problem. First, do all the work within parentheses. Second, evaluate any exponents. Third, multiply and divide in order from left to right. Fourth, add and substract, in order form left to right.
1. Wendell needed to evaluate the expresion 52−3×8×2 . a. Circle the operation below that must be done first. Addition
Substraction
Multiplication
Division
Exponents
b. Wendell said that the first needed to find the product of 8 and 2. Is Wendell's statement correct? Explain your answer.
2. Using the rules for the order of operations evaluate each of the following expressions. a. 5×36÷3−7 b. 524÷6−8 c. 34×5−6 d. 30÷5×6
3. Jose works for $9 an hour and gets paid every three weeks. The first week he worked 7 hours, the second week he worked 9 hours, and the third week he worked 10 hours. a. Write an expression to show how much Jose's paycheck will be. b. Evaluate your expression.
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