Common Mistakes on the ASVAB (Armed Services Vocational Aptitude Battery)

Note: The ASVAB is unique because it determines both your military enlistment eligibility (AFQT score) and your job qualifications (Line Scores) . High school students often take it, but so do adult enlistees.

A. Arithmetic Reasoning (AR): The "Word Problem" Wall

This is the most important section for your AFQT score, but it's also where people lose the most points.

• Mistake 1: Doing the Math Before Understanding the Question

  • Scenario: "A train leaves Station A at 60 mph. Another train leaves Station B at 70 mph..." The student immediately starts calculating speed and distance, only to realize the question actually asks, "What time do they meet?" but they forgot to account for the time zone difference mentioned in the text.

  • Fix: Cover the numbers. Read the sentence containing the question mark first. Underline exactly what they want (e.g., "total cost," "remaining distance," "average speed"). Then go back and find the numbers you need.

• Mistake 2: Forgetting to Round

  • Scenario: The math works out to 23.6 gallons. The answer choices are 23, 24, 25, and 26.

  • Fix: Look at the context. If it's "how many gallons to fill the tank," you need to round up to 24, because you can't buy 0.6 of a gallon at a gas station. If it's "how many buses are needed for a trip," you must round up to the nearest whole bus. Context dictates rounding.

B. Mathematics Knowledge (MK): The "Simple Algebra" Slip

• Mistake 3: Sign Errors in Basic Equations

  • Scenario: Solving for x in -2x + 4 = 10. The student subtracts 4 from both sides to get -2x = 6, but then divides and forgets the negative sign, getting x = 3 instead of x = -3.

  • Fix: On scratch paper, circle the variable you are solving for and draw an arrow to the sign in front of it. Train yourself to check your answer by plugging it back into the original equation.

C. Word Knowledge (WK): The "Sounds Like" Trap

• Mistake 4: Confusing Similar Words

  • Scenario: The word is "affect." The student sees the answer choices: (A) Change, (B) Result, (C) Pretend, (D) Trick. They pick (B) Result because they are thinking of "effect."

  • Fix: If you are unsure, break the word down. Use the sentence in the question (if provided) to see how the word functions. ASVAB vocabulary often tests commonly confused pairs (e.g., imminent/eminent, accept/except).

D. Mechanical Comprehension (MC): The "Common Sense" vs. "Physics" Battle

• Mistake 5: Relying on Intuition Instead of Principles

  • Scenario: A question shows two gears meshed together. A small gear is turning clockwise. The question asks which way the large gear turns. A student might think the large gear turns slower, so maybe it turns the opposite way? (They are correct, it turns counter-clockwise). But on a harder question involving a block-and-tackle pulley system, intuition often fails.

  • Fix: For mechanical advantage questions, don't guess. Count the number of ropes supporting the moving load. That number is your mechanical advantage. Intuition will trick you into thinking more ropes = harder to pull, when actually it's the opposite.