OAR Math Skills Test: Adaptive Math on the ASTB-E

What's published, and what isn't

Source: NMOTC ASTB-E Overview and FAQ. Because the real length and clock aren't published, our set uses a fixed length and timing we chose. Treat its clock as practice pressure, not a forecast.

How the OAR treats your math

Adaptive means each question depends on how you've answered so far, so two candidates can see different questions and different counts. Finish too few before time expires and a penalty may be applied, and NMOTC advises against random guessing as time runs out.

Your MST result combines with reading and mechanical comprehension into the OAR, scored 20–80 in one-point steps. The formula is proprietary and compensatory. NMOTC publishes no OAR passing score; each program sets its own minimum (for example, NPC Program Authorizations 106/107). Any OAR figure in our app is an estimate.

Retests carry a catch: three attempts at most, at least 30 full calendar days apart, and your most recent attempt replaces all earlier scores, even higher ones.

What it tests

Arithmetic, algebra, geometry and simple probability, as plain equations and as word problems, like the speed-and-distance problem in knots below.

The technique: check before you click

With no going back, the last ten seconds of a question are worth more than the first. Solve, then run a fast check before you commit: is the unit right, is the size sensible, and does the answer respond to what was asked? A slip you'd catch on review is permanent here.

Three worked examples

1. Time from speed and distance. A ship makes 16 knots. How long does it take to cover 56 nautical miles? Options: 2 h 50 min, 3 h 20 min, 3 h 30 min, 3 h 50 min, 4 h 30 min. A knot is one nautical mile per hour, so time = 56 ÷ 16 = 3.5 hours = 3 h 30 min. Check: 16 × 3.5 = 56. The trap reads 3.5 hours as 3 h 50 min.

2. Probability. A box holds 4 red, 5 blue and 3 green markers. You draw one at random. What is the probability it is not blue? Options: 5/12, 1/2, 7/12, 3/4, 7/5. Seven of the 12 markers aren't blue, so 7/12. Check: 7/12 + 5/12 = 1. And 7/5 is more than 1, which no probability can be.

3. Geometry. A rectangle's length is twice its width, and its perimeter is 54 cm. What is its area? Options: 81, 108, 144, 162, 324 cm². With width w, 2(w + 2w) = 54, so w = 9 and the length is 18. Area = 9 × 18 = 162 cm². Check: 2(9 + 18) = 54. The 81 and 324 traps square one side instead of multiplying the two.

Traps

• Hurrying to the next screen. There's no second look, so spend the ten seconds now.
• Decimal hours. 0.5 h is 30 minutes and 0.25 h is 15, not 50 or 25.
• Perimeter vs area. Note which one the question wants before you start.
• Clicking at random as time runs out. NMOTC advises against it on adaptive subtests.

Pacing without a published clock

With no published time limit, pace by habit: keep moving, never let one question stall you, and reach the end steady rather than rushed. In our timed set, 30 questions in 25 minutes is 50 seconds each, a brisk rhythm to train against.

Practice it here

Our practice doesn't adapt the way APEX does: every set has a fixed length, and the timing is ours. Use practice mode for an explanation after each answer, then the timed set. Our timed sets let you skip and return; the real section won't, so treat every answer as final. Questions are original. Also taking the Army's SIFT? Its math test has a published 40-minute limit; see SIFT Math Skills.

How to answer an OAR math question you can't revisit

1. Read what is asked, and in what unit, before you calculate.
2. Set up the equation or ratio on scratch paper.
3. Estimate, so you know roughly what size of answer to expect.
4. Solve with the simplest arithmetic you can.
5. Check: plug the answer back in, confirm the unit, and make sure it answers the question asked.
6. Click only after the check; you can't change the answer later.

FAQ