Praxis Core Academic Skills for Educators: Mathematics (5733)Number and QuantityEasy
A student is calculating the value of an expression: 3^2 + (15 - 3) ÷ 4. What is the correct value?
- A9
- B6
- C12
- D14
Show answer & explanationAnswer & explanation
Correct answer: C. 12
Follow the order of operations (PEMDAS/BODMAS): 1. Parentheses/Brackets: (15 - 3) = 12. 2. Exponents/Orders: 3^2 = 9. 3. Division: 12 ÷ 4 = 3. 4. Addition: 9 + 3 = 12.
Why the other options are wrong
- A. This might result from stopping after the exponent or errors in division/addition.
- B. This might result from incorrect order of operations, perhaps adding before dividing or miscalculating 3^2.
- D. This might result from performing operations from left to right without respecting the order of operations.
Order of Operations (PEMDAS/BODMAS)
PEMDAS (Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right)) is the standard sequence for performing mathematical operations in an expression.
- Parentheses/Brackets first.
- Exponents/Orders second.
- Multiplication and Division are equal priority, done left to right.
- Addition and Subtraction are equal priority, done left to right.
Memory trick: Please Excuse My Dear Aunt Sally!