What the task is
You get a system of simple equations. Each letter stands for a whole number, and exactly one solution satisfies every equation. Your job is to find the value the question asks for.
Substitution beats algebra here
- Find the equation that already gives a value, or a direct relation such as one letter equals another plus one.
- Push that value through the other equations one at a time.
- Stop as soon as the asked letter is known. You do not have to solve the whole system.
- Use the number range as an error check: a value outside the allowed whole-number range means a slip.
Mental arithmetic under pressure
- Round and check: if a product looks close but not exact, recheck before choosing.
- Keep one running value in your head at a time. Chains of three or more are where errors creep in.
- No calculator is allowed, so practise the same way from the start.
The number of items and the time limit for this subtest are not confirmed in the public preparation materials. The other two Core subtests are 25 minutes for 20 items each, so DMATBLAZE practice assumes the same pace. Check the official instructions video before your exam.
A worked example
Suppose the system is:
- A + B = 9
- B = A + 3
- C = A x B
Asked: the value of C.
- The second equation is a direct relation, so substitute it into the first: A + (A + 3) = 9.
- That gives 2A + 3 = 9, so 2A = 6 and A = 3.
- Then B = 3 + 3 = 6. Check against the first equation: 3 + 6 = 9. Correct.
- Finally C = 3 x 6 = 18. Stop here; nothing else needs solving.
Notice the order: start from the equation that already gives a relation, not from the equation that contains the asked letter. The check in step 3 costs two seconds and catches most slips.
Common questions
How do I solve dMAT equation systems quickly?
Start from the equation that gives a value or a direct relation, substitute it into the others, and stop as soon as the asked letter is known.
Can I use a calculator in the dMAT?
No. The official materials state that no helping tools are available in the exam.