Question

Prof. Schaben asks her students to simplify this expression: 21 space plus space 15 space divided by space 3. Cecilia's answer is 12. Is this the correct answer? Why or why not?

Answer 1

Cecilia's answer is 12 which is incorrect. The correct answer is 26.

Explanation:

Given:

Prof. Schaben asks her students to simplify this expression:

21 space plus space 15 space divided by space 3.

Cecilia's answer is 12.

Now, to find whether the answer is correct or not.

As the expression given:

21 space plus space 15 space divided by space 3.

21 + 15 ÷ 3.

So, we solve it by using the PEMDAS rule:

According to P E M D A S first is division then addition.

Thus, the solution will be as:

`21\ +\ 15\ /\ 3.`

`=21\ +\ 5.`

`=26.`

Hence, the correct answer is 26.

Therefore, Cecilia's answer is 12 which is incorrect. The correct answer is 26.