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Evaluate expressStephen tried to evaluate the expression (8 + 6 x 2) - 4. His work is below.[8 + 6 x 2] =4Step 1: = [8+ 12) = 4Step 2:= 8 +3Step 3:= 11In which step did Stephen first make a mistake?Choose 1 answer:Step 1Step 2Step 3

Evaluate expressStephen tried to evaluate the expression (8 + 6 x 2) - 4. His work-example-1
User Scott Colby
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1 Answer

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Step 1

State the rule for solving such expressions


\begin{gathered} \text{PEMDAS} \\ P-\text{Parenthesis} \\ E-\text{exponential} \\ M-Mu\text{ltiplication} \\ D-\text{Division} \\ A-\text{ Addition} \\ S-\text{ Subtraction} \end{gathered}

Step 2

Find Stephen's mistake

From the expression


\begin{gathered} \lbrack8+6*2\rbrack/4 \\ \text{Stephen will try to clear the parenthesis first and to do so he must multiply within the parenthesis first} \\ \lbrack8+12\rbrack/4 \\ \text{Hence, his first step is right} \end{gathered}
\begin{gathered} Next,\text{ he will go further to clear the remains of the parenthesis by adding 8 to 12}. \\ 20/4 \\ \text{Instead he failed to clear the parenthesis totally, dividing 12 in the parenthesis by 4.} \end{gathered}

This wrongly made his step 2 to be 8 + 3.

Hence, the first mistake he made was in step 2

User Jenessa
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