Answer: Step 5
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Reason:
The order of operations is PEMDAS
- P = parenthesis
- E = exponents
- M = multiplication
- D = division
- A = addition
- S = subtraction
The multiplication and division are on the same level of precedent, and the same goes for addition and subtraction. Some math textbooks may refer to PEMDAS as BODMAS, which is basically the same thing.
Notice how division comes before addition. So we must compute the portion first before adding in step 4.
This is what steps 4 and onward should look like
So that's why the error is in <u>step 5</u>
If there was parenthesis around the "2+10", and we had , then step 5 given by your teacher would be correct.