RankHighCompetitive Exam Prep

Numbers

Number facility

Performing given arithmetic — addition, subtraction, multiplication, division — quickly and accurately. The operation is already determined; the measure is execution.

Exams on RankHigh that test this

What follows is our approach, not an official rule. What each question type measures is set by the body that runs the examination. How to work one is RankHigh’s method — it is what a good tutor would tell you, and there is more than one way to be right. Where an examination publishes its own instructions, those govern on the day.

Number Facility

Tested as “Number Facility” on CDCR Correctional Officer, NYC Correction Officer.

Doing straightforward arithmetic quickly and getting it exactly right, under time pressure and without a calculator.

Where people lose it

Rushing the easy ones. These questions are not difficult, which is precisely why they are lost — a transposed digit or a dropped carry costs the same mark as a question you could not do at all.

How to work itRankHigh method

  1. Read what is being asked for BEFORE you start calculating. Half the errors here are correct arithmetic answering the wrong question.
  2. Estimate first. Knowing the answer is near 400 catches the slip that produces 40 or 4,000.
  3. Line the numbers up by place value rather than working across a sentence.
  4. Check the last digit. It is the cheapest verification there is and it catches most transpositions.

The arithmetic is not the hard part. Not rushing it is.

Basic Math – Addition/Subtraction

Tested as “Basic Math – Addition/Subtraction” on BSCC/STC Corrections Entry.

Adding or subtracting a set of whole numbers accurately.

Where people lose it

Working too fast on carries and borrows. Every wrong option is built from a specific, real arithmetic slip — a dropped carry, a misread digit, an off-by-one borrow — not a random number.

How to work itRankHigh method

  1. Align the numbers by place value before adding or subtracting, whether the problem is shown vertically or inline.
  2. Work right to left, one column at a time, and write down each carry or borrow rather than tracking it in your head.
  3. Check your answer's last digit against the ones-column arithmetic alone as a fast sanity check.
  4. If your answer matches an option exactly, verify the operation was the one asked for — addition and subtraction distractors sometimes swap the operation.

Slow down on carries and borrows specifically — that is where every wrong option comes from.

Carry this into the room

  • Number Facility: The arithmetic is not the hard part. Not rushing it is.
  • Basic Math – Addition/Subtraction: Slow down on carries and borrows specifically — that is where every wrong option comes from.

Practice it on your own exam

Method only sticks against real questions. Every exam in the catalog opens with a free twelve-question diagnostic — in your browser, with a worked explanation for every answer, and no signup.

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