Select the correct answer.

A mistake was made in the steps shown to simplify the expression. Which step includes the mistake?

[tex] \frac{1+3^2}{5} + |-10| \div 2 [/tex]

Step 1: [tex] \frac{1+3^2}{5} + 10 \div 2 [/tex]

Step 2: [tex] \frac{1+9}{5} + 10 \div 2 [/tex]

Step 3: [tex] \frac{10}{5} + 10 \div 2 [/tex]

Step 4: [tex] 2 + 10 \div 2 [/tex]

Step 5: [tex] 2 + 5 [/tex]

Step 6: [tex] 7 [/tex]

A. Step 4

B. Step 5

C. Step 3

D. Step 1



Answer :

To analyze the steps and identify where the mistake occurs, let's go through each step carefully:

The initial expression is:
[tex]\[ \frac{1 + 3^2}{5} + |-10| \div 2 \][/tex]

Step 1:
[tex]\[ \frac{1 + 3^2}{5} + 10 \div 2 \][/tex]
This step simplifies [tex]\( |-10| \)[/tex] correctly to [tex]\( 10 \)[/tex]. No mistake here.

Step 2:
[tex]\[ \frac{1 + 9}{5} + 10 \div 2 \][/tex]
This step simplifies [tex]\( 3^2 \)[/tex] to [tex]\( 9 \)[/tex]. No mistake here.

Step 3:
[tex]\[ \frac{10}{5} + 10 \div 2 \][/tex]
This step adds [tex]\( 1 + 9 \)[/tex] to get [tex]\( 10 \)[/tex] in the numerator. No mistake here.

Step 4:
[tex]\[ 2 + 10 \div 2 \][/tex]
This step simplifies [tex]\( \frac{10}{5} \)[/tex] to [tex]\( 2 \)[/tex]. No mistake here in the division part but we need to pay attention to the order of operations in the next step.

Step 5:
[tex]\[ 12 \div 2 \][/tex]
This step adds [tex]\( 2 + 10 \)[/tex], which is incorrect because division should be performed before addition, following the order of operations (PEMDAS/BODMAS). The correct approach would have been to perform the division first:
[tex]\[ 2 + 5 = 7 \][/tex]

Given this mistake in Step 5, Step 5 is where the mistake occurs.

The correct answer is:
B. Step 5