Whole Number Operations
What you must know
Whole number questions test the four operations (addition, subtraction, multiplication, division) plus place value and the order of operations. You should be fluent with multi-digit multiplication and long division, comfortable rounding, and able to apply the standard order of operations: parentheses, exponents, multiplication and division left to right, then addition and subtraction left to right.
Common traps
- Order of operations: In an expression like 6 + 2 × 5, multiply first to get 16, not 40. Work strictly left to right within the same tier.
- Subtraction with borrowing: When a digit in the top number is smaller than the digit below it, regroup from the next place value.
- Division remainders: Read carefully whether a question asks for the quotient, the remainder, or the number of full groups needed (which may require rounding up).
- Rounding: Round only at the end of a multi-step problem; rounding early distorts the answer.
- Estimation checks: A quick estimate catches place-value slips.
Worked example
Compute 48 ÷ 6 + 3 × (7 − 2). Parentheses first: 7 − 2 = 5, so the expression is 48 ÷ 6 + 3 × 5. Multiply/divide left to right: 48 ÷ 6 = 8 and 3 × 5 = 15. Add: 8 + 15 = 23.
Rule of thumb
Estimate first, then compute exactly, then compare. If your exact answer is far from the estimate, recheck the place values you wrote down.