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] = 12 \div 2 [/tex]

Step 6: [tex] = 6 [/tex]

A. Step 1
B. Step 3
C. Step 4
D. Step 5



Answer :

Let's go through each step of the given expression to identify where the mistake lies.

We start with the original expression:
[tex]\[ \frac{1+3^2}{5}+|-10| \div 2 \][/tex]

Step 1:
[tex]\[ \frac{1+3^2}{5}+10 \div 2 \][/tex]
In this step, the absolute value of [tex]\(-10\)[/tex] has been correctly evaluated to [tex]\(10\)[/tex]. This is correct.

Step 2:
[tex]\[ \frac{1+9}{5}+10 \div 2 \][/tex]
Next, [tex]\(3^2\)[/tex] is evaluated as [tex]\(9\)[/tex]. The expression now is properly written as [tex]\(\frac{1+9}{5} + 10 \div 2\)[/tex]. This is also correct.

Step 3:
[tex]\[ \frac{10}{5}+10 \div 2 \][/tex]
Here, [tex]\(1+9\)[/tex] has been summed to give [tex]\(10\)[/tex]. Dividing [tex]\(10\)[/tex] by [tex]\(5\)[/tex] will give us [tex]\(2\)[/tex]. This step is accurate if we write it out first; however, the division operation of 10 by 5 in the form of [tex]\(\frac{10}{5}\)[/tex] gives the correct initial value for our simplified step next. So far, so good.

Step 4:
[tex]\[ 2+10 \div 2 \][/tex]
At this step, [tex]\(\frac{10}{5}\)[/tex] is rightly calculated to be [tex]\(2\)[/tex]. Here, it should now separately handle division next correctly.

Step 5:
[tex]\[ 2+5 \][/tex]
The division [tex]\(10 \div 2\)[/tex] should yield [tex]\(5\)[/tex]; adding this value to [tex]\(2\)[/tex] correctly becomes [tex]\(2 + 5 = 7\)[/tex].

The problem lies in the continuation past the correct calculation and merging operations together here could lead to incorrect simplification not reflecting step splitting right.

About Mistake:
However, if strict divide operation treated, typically steps wrongly merged over breaking simplified here:
Incorrect here drastically over:
Instead:
\

Final Correct step 5:

Formula thus [tex]\(\boxed{\text{Result 5}\sim 7 }: [not valid 6 Simplified only whole true rest split phase tab erroneous] this ensures true validation confirming step here bracket right methodically. """ Given clear phase \(\boxed{\text{D}}\)[/tex].
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