AIMO Preparation — Free Diagnostic Mock

15-question diagnostic · AIMO · integer answers · Number Theory / Geometry / Algebra / Combinatorics
🎁 FREE Diagnostic

15 questions to find exactly where your AIMO problem-solving is strong — and where it's not

This is a free diagnostic for the AIMO Preparation course (Australian Intermediate Mathematics Olympiad). 15 real AIMO-style problems (integer answers, 0–999) sample Number Theory, Geometry, Algebra and Combinatorics.

It's an exam: answer all the questions first (you can change any answer freely), then submit the whole exam to see your report. The worked solutions and hints unlock only after you submit. Use the jump menu at the top to move around.

At the end you get a knowledge-point report: a bar for every topic you attempted, your weak spots flagged, and the exact lessons to revise.

  • ~15 minutes. No login needed. No marks deducted for a wrong answer — never leave one blank.
  • Self-paced, no time limit — but try to commit to an answer before you review, just like a real test.

Year 8–12 students preparing for AIMO selection.

⭐ Q1AIMOInteger answerAIMO › Number Theory
The Problem

Let x denote a single digit. The tens digit in the product of 2x7 and 39 is 9. Find x .

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Number Theory problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 8

Revise: the AIMO Number Theory pathway in the full course.

⭐ Q2AIMOInteger answerAIMO › Number Theory
The Problem

If n is a positive integer and \(n^{2}\) equals the 4-digit number aabb , find n .

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Number Theory problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 88

Revise: the AIMO Number Theory pathway in the full course.

⭐ Q3AIMOInteger answerAIMO › Number Theory
The Problem

A 3-digit number abc is multiplied by 3 to give the 4-digit number c0ba . Find the number abc .

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Number Theory problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 351

Revise: the AIMO Number Theory pathway in the full course.

⭐ Q4AIMOInteger answerAIMO › Number Theory
The Problem

The n-th triangular number is the sum of the first n positive integers. Let T n denote the sum of the first n triangular numbers. Derive a formula for T n . For the input below: compute T 10 (the sum of the first 10 triangular numbers).

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Number Theory problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 220

Revise: the AIMO Number Theory pathway in the full course.

⭐ Q5AIMOInteger answerAIMO › Number Theory
The Problem

The $n$th triangular number is $t_n = \tfrac{n(n+1)}{2}$. Notice that $t_1 + t_9 = 1 + 45 = 46 = 10 + 36 = t_4 + t_8$, so $46$ is a sum of two triangular numbers in two different ways. Submit this common value $t_1 + t_9 = t_4 + t_8$.

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Number Theory problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 46

Revise: the AIMO Number Theory pathway in the full course.

⭐ Q6AIMOInteger answerAIMO › Number Theory
The Problem

Determine the number of non-negative integers x that satisfy the equation ⌊x/44⌋ = ⌊x/45⌋ .

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Number Theory problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 990

Revise: the AIMO Number Theory pathway in the full course.

⭐ Q7AIMOInteger answerAIMO › Geometry
The Problem

Triangles \(ABC\) and \(XYZ\) are congruent right-angled isosceles triangles. A square \(KLMB\) is inscribed in \(\triangle ABC\) with two sides along the legs (one corner at the right angle); a square \(PQRS\) is inscribed in \(\triangle XYZ\) with one side along the hypotenuse. If the area of \(KLMB\) is \(189\), find the area of \(PQRS\).

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Geometry problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 168

Revise: the AIMO Geometry pathway in the full course.

⭐ Q8AIMOInteger answerAIMO › Geometry
The Problem

A rectangle has sides of length \(28\) and \(15\). One diagonal is divided into \(7\) equal parts by \(6\) points, and every division point is joined to the two opposite corners. This cuts the rectangle into \(7\) quadrilaterals. Find the area of one of them, the quadrilateral \(DEBF\).

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Geometry problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 60

Revise: the AIMO Geometry pathway in the full course.

⭐ Q9AIMOInteger answerAIMO › Geometry
The Problem

A triangle \(ABC\) is divided into four regions by three lines parallel to \(BC\). The lines divide \(AB\) into four equal segments. If the second largest region has area \(225\), what is the area of \(\triangle ABC\)?

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Geometry problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 720

Revise: the AIMO Geometry pathway in the full course.

⭐ Q10AIMOInteger answerAIMO › Geometry
The Problem

Consider a circular sector of radius $360$ which is one-sixth of a circle. A circle is drawn inside this sector so that it is tangent to the two radii and to the circular arc. Calculate the radius of this smaller circle.

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Geometry problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 120

Revise: the AIMO Geometry pathway in the full course.

⭐ Q11AIMOInteger answerAIMO › Geometry
The Problem

$ABCD$ is a trapezium for which $AB \parallel DC$, $AB = 84$ and $DC = 25$. A circle can be drawn in the trapezium so that it just touches all four sides. Find the perimeter of the trapezium.

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Geometry problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 218

Revise: the AIMO Geometry pathway in the full course.

⭐ Q12AIMOInteger answerAIMO › Geometry
The Problem

A circle is inscribed in a hexagon $ABCDEF$ so that each side of the hexagon is tangent to the circle. Find the perimeter of the hexagon if $AB = 6$, $CD = 7$, and $EF = 8$.

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Geometry problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 42

Revise: the AIMO Geometry pathway in the full course.

⭐ Q13AIMOInteger answerAIMO › Algebra
The Problem

Asha, Bree and Cala are three robots that are programmed to run athletic track races. When Asha runs a 400 m race she catches Bree at the finish line, if Bree starts 20 m ahead of Asha. Asha catches Cala at the finish line of a 1500 m race, if Cala has a 246 m start. Assuming each robot runs at constant speed, how many metres must Cala start ahead of Bree in an 800 m race, if they are to finish at the same time?

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Algebra problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 96

Revise: the AIMO Algebra pathway in the full course.

⭐ Q14AIMOInteger answerAIMO › Algebra
The Problem

Gaston and Jordon always misread cooking times. If the required time is “1:32” (1 hour 32 minutes), Jordon reads it as 132 minutes while Gaston reads it as 1.32 hours. For one particular recipe, the difference between Jordon's and Gaston's misread times is exactly 90 minutes. What is the actual cooking time, in minutes?

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Algebra problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 145

Revise: the AIMO Algebra pathway in the full course.

⭐ Q15AIMOInteger answerAIMO › Algebra
The Problem

A school adds 5 extra classrooms enabling 5 more classes and reducing the average class size by 6. Two months later another 5 classrooms are added, again enabling 5 more classes, this time reducing average class size by 4. The number of students did not change. How many students were at the school?

Your answer

❓ Enter your answer (a whole number):

🎯 Knowledge Point — what this tests

An AIMO Algebra problem (integer answer 0–999). Set up the relationship carefully and compute — AIMO rewards a clean, checkable method.

Work the problem to a single whole number, then check it against the conditions.

✅ Answer: 600

Revise: the AIMO Algebra pathway in the full course.

🏁 Finish

That's the end of the exam

Go back and change any answers you like. When you're ready, submit the whole exam to lock it in and see your knowledge report — then you can revisit every question to read the full worked solution.

The report stays locked until you submit — you can't open it early.

📊 Diagnostic Report

Your knowledge-point report

Here is how you performed on every knowledge area you attempted. Bars show your accuracy per topic — green is strong, amber is shaky, red needs work. Only questions you answered are scored.

Know another parent preparing too?
Send them this free diagnostic — it shows any child exactly where they're strong and where to focus. Pure help, nothing to buy.

Want to turn the red and amber bars green? The full AIMO Preparation course builds AIMO problem-solving across Number Theory, Geometry, Algebra and Combinatorics.

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