Class 6 Maths Olympiad: 40 Questions with Answers (2026)

Class 6 Maths Olympiad: 40 Practice Questions with Answers

Practise 40 original Class 6 Maths Olympiad questions with clear worked solutions. These questions cover number systems, whole numbers, factors, integers, fractions, decimals, geometry, measurement, data handling, algebra, ratio and reasoning. Every answer appears directly below its question, so you can study without downloading a file or finding a separate answer key.

Use this guide for understanding and revision. It is an independently written practice set, not an official previous-year examination paper. The topic selection draws from the School Connect Olympiad Class 6 Maths chapters and its 2026 syllabus. For other Olympiad organisers, check their own rules and curriculum.

How to practise effectively

Choose an answer before reading the explanation.
Show a calculation, diagram or brief reason for your choice.
Compare your method with the worked answer below.
When you make a mistake, practise a new question on the same concept.
Work through one topic section at a time if a full set feels too long.

Knowing our numbers

Question 1. Which number is greatest?
A. 709,850 | B. 790,805 | C. 790,850 | D. 709,805
Answer: C. 790,850. Compare the hundred-thousands, then ten-thousands, then smaller places. Of the 790-thousand numbers, 790,850 is greater than 790,805.
Question 2. What is the place value of 8 in 5,834,271?
A. 8,000 | B. 80,000 | C. 800,000 | D. 8,000,000
Answer: C. 800,000. The 8 is in the hundred-thousands place. Its value is 8 × 100,000 = 800,000.
Question 3. Estimate 48,620 + 31,480 by rounding each number to the nearest thousand.
A. 79,000 | B. 80,000 | C. 81,000 | D. 90,000
Answer: B. 80,000. 48,620 rounds to 49,000 and 31,480 rounds to 31,000. The estimated sum is 80,000.
Question 4. Which number is the smallest six-digit number using the digits 0, 2, 4, 5, 7 and 8 exactly once?
A. 204,578 | B. 240,578 | C. 204,587 | D. 205,478
Answer: A. 204,578. A six-digit number cannot begin with zero. Choose 2 first, then arrange the rest in ascending order: 0, 4, 5, 7, 8.

Whole numbers

Question 5. Find 398 × 25.
A. 9,550 | B. 9,950 | C. 9,980 | D. 10,050
Answer: B. 9,950. Use 398 × 25 = (400 − 2) × 25 = 10,000 − 50 = 9,950.
Question 6. What is 3,600 ÷ 45?
A. 70 | B. 75 | C. 80 | D. 90
Answer: C. 80. 45 × 8 = 360, so 45 × 80 = 3,600. The quotient is 80.
Question 7. What is 6 × (18 + 12)?
A. 180 | B. 108 | C. 120 | D. 150
Answer: A. 180. First add inside brackets: 18 + 12 = 30. Then 6 × 30 = 180.
Question 8. What number comes next: 2, 6, 12, 20, 30, __?
A. 36 | B. 40 | C. 42 | D. 44
Answer: C. 42. The terms are n(n+1): 1×2, 2×3, 3×4, 4×5, 5×6. The next is 6×7 = 42.

Playing with numbers

Question 9. What is the greatest common factor (HCF) of 36 and 48?
A. 6 | B. 9 | C. 12 | D. 18
Answer: C. 12. Common factors include 1,2,3,4,6 and 12; 12 is the greatest.
Question 10. What is the least common multiple (LCM) of 8 and 12?
A. 16 | B. 20 | C. 24 | D. 36
Answer: C. 24. Multiples of 8 are 8,16,24; multiples of 12 are 12,24. The first shared multiple is 24.
Question 11. Which number is divisible by both 3 and 5?
A. 205 | B. 210 | C. 212 | D. 221
Answer: B. 210. A number divisible by 5 ends in 0 or 5. For 210 the digit sum is 2+1+0=3, so it is also divisible by 3.
Question 12. What is the prime factorisation of 84?
A. 2 × 3 × 14 | B. 2 × 2 × 3 × 7 | C. 3 × 4 × 7 | D. 2 × 6 × 7
Answer: B. 2 × 2 × 3 × 7. 84 = 2 × 42 = 2 × 2 × 21 = 2 × 2 × 3 × 7. Every factor listed is prime.

Integers

Question 13. What is −8 + 13?
A. −21 | B. −5 | C. 5 | D. 21
Answer: C. 5. Starting at −8 on a number line, move 13 places right to reach 5.
Question 14. What is −6 − 9?
A. −15 | B. −3 | C. 3 | D. 15
Answer: A. −15. Subtracting 9 from −6 means moving 9 more units left: −15.
Question 15. Which number is greatest?
A. −7 | B. −2 | C. −5 | D. −10
Answer: B. −2. Among negative numbers, the value closest to zero is greatest. Therefore −2 is greatest.

Fractions

Question 16. Calculate 3/4 + 1/8.
A. 4/12 | B. 7/8 | C. 1/2 | D. 5/8
Answer: B. 7/8. Convert 3/4 to 6/8. Then 6/8 + 1/8 = 7/8.
Question 17. Calculate 5/6 − 1/3.
A. 1/6 | B. 1/2 | C. 2/3 | D. 4/9
Answer: B. 1/2. Replace 1/3 with 2/6. Then 5/6 − 2/6 = 3/6 = 1/2.
Question 18. What is 2/5 of 60?
A. 12 | B. 20 | C. 24 | D. 30
Answer: C. 24. One fifth of 60 is 12. Two fifths is 2 × 12 = 24.

Decimals

Question 19. What is 7.85 + 2.6?
A. 9.45 | B. 10.45 | C. 10.85 | D. 11.45
Answer: B. 10.45. Write 2.6 as 2.60, then add: 7.85 + 2.60 = 10.45.
Question 20. What is 12.5 − 4.78?
A. 7.62 | B. 7.72 | C. 8.72 | D. 8.28
Answer: B. 7.72. Use 12.50 − 4.78 = 7.72 after aligning decimal places.

Ratio and proportion

Question 21. The ratio of blue to red beads is 3:4. If there are 21 blue beads, how many red beads are there?
A. 24 | B. 25 | C. 28 | D. 30
Answer: C. 28. Three equal parts represent 21, so one part is 7. Four parts represent 4 × 7 = 28 red beads.
Question 22. Four notebooks cost 60 units. How much would seven notebooks cost at the same rate?
A. 90 units | B. 105 units | C. 110 units | D. 120 units
Answer: B. 105 units. One notebook costs 60 ÷ 4 = 15 units, so seven cost 7 × 15 = 105 units.
Question 23. What is 25% of 200?
A. 25 | B. 40 | C. 50 | D. 75
Answer: C. 50. 25% means one quarter. One quarter of 200 is 50.
Question 24. A class has 18 girls and 12 boys. What is the ratio of girls to boys in simplest form?
A. 2:3 | B. 3:2 | C. 6:4 | D. 18:30
Answer: B. 3:2. Girls : boys is 18:12. Divide both by six to obtain 3:2.
Question 25. If five kilograms of rice cost 300 units, how much do two kilograms cost at the same unit price?
A. 100 units | B. 120 units | C. 150 units | D. 180 units
Answer: B. 120 units. One kilogram costs 300 ÷ 5 = 60 units, so two kilograms cost 120 units.

Geometry and angles

Question 26. How many degrees are there in a right angle?
A. 45° | B. 60° | C. 90° | D. 180°
Answer: C. 90°. A right angle measures exactly 90 degrees.
Question 27. What is the complementary angle of 35°?
A. 45° | B. 55° | C. 65° | D. 145°
Answer: B. 55°. Complementary angles sum to 90 degrees; 90 − 35 = 55.
Question 28. Two angles in a triangle are 50° and 60°. What is the third angle?
A. 60° | B. 65° | C. 70° | D. 80°
Answer: C. 70°. The interior angles of a triangle total 180°. Therefore the last angle is 180 − 50 − 60 = 70°.
Question 29. Three angles in a quadrilateral are 90°, 80° and 95°. Find the fourth angle.
A. 85° | B. 90° | C. 95° | D. 105°
Answer: C. 95°. A quadrilateral’s interior angles total 360°. The known angles total 265°, so the last is 360 − 265 = 95°.
Question 30. Which describes a line segment?
A. It has no endpoints | B. It has exactly one endpoint | C. It has two endpoints | D. It can never be measured
Answer: C. It has two endpoints. A line segment is the straight portion of a line between two endpoints and has a measurable length.

Mensuration and symmetry

Question 31. A rectangle measures 14 cm by 9 cm. What is its perimeter?
A. 23 cm | B. 46 cm | C. 126 cm | D. 42 cm
Answer: B. 46 cm. Perimeter = 2 × (14 + 9) = 46 cm.
Question 32. What is the area of a rectangle 12 cm long and 7 cm wide?
A. 19 square cm | B. 38 square cm | C. 84 square cm | D. 96 square cm
Answer: C. 84 square cm. Area = length × breadth = 12 × 7 = 84 square centimetres.
Question 33. A triangle has base 10 cm and height 6 cm. What is its area?
A. 30 square cm | B. 60 square cm | C. 16 square cm | D. 40 square cm
Answer: A. 30 square cm. Area of triangle = half × base × height = 1/2 × 10 × 6 = 30 square centimetres.
Question 34. A square has perimeter 52 cm. How long is each side?
A. 12 cm | B. 13 cm | C. 14 cm | D. 26 cm
Answer: B. 13 cm. All four sides are equal. Divide 52 by four to get 13 cm per side.
Question 35. How many lines of symmetry does a rectangle that is not a square have?
A. 1 | B. 2 | C. 4 | D. 0
Answer: B. 2. A non-square rectangle has two symmetry lines: one horizontal and one vertical through its centre.

Data, algebra and reasoning

Question 36. A pictograph key says one star represents 3 books. What do six stars represent?
A. 9 books | B. 12 books | C. 18 books | D. 21 books
Answer: C. 18 books. Each star stands for three books. Six stars mean 6 × 3 = 18 books.
Question 37. Find the average of 5, 7, 9 and 11.
A. 7 | B. 8 | C. 9 | D. 10
Answer: B. 8. Sum = 5 + 7 + 9 + 11 = 32. Divide by four numbers to obtain 8.
Question 38. If x + 9 = 23, what is x?
A. 12 | B. 13 | C. 14 | D. 15
Answer: C. 14. Subtract nine from both sides: x = 23 − 9 = 14.
Question 39. If a = 4, what is the value of 2a + 3?
A. 7 | B. 8 | C. 11 | D. 14
Answer: C. 11. Replace a with 4: 2 × 4 + 3 = 8 + 3 = 11.
Question 40. Find the next number in the pattern 3, 8, 15, 24, 35, __.
A. 42 | B. 46 | C. 48 | D. 50
Answer: C. 48. The differences are 5, 7, 9, 11. The next difference is 13, giving 35 + 13 = 48.

How to revise after the 40 questions

Question range	Topics	Next learning activity
1–4	Large numbers, place value and estimation	Use digit cards to make, compare and round six-digit numbers
5–8	Whole-number operations and patterns	Explain each calculation using the distributive property or patterns
9–12	Factors, multiples and divisibility	List factors and use a number grid to find common multiples
13–20	Integers, fractions and decimals	Use a number line and common denominators to check answers
21–25	Ratio, unitary method and percentages	Draw equal-part bars or calculate the value of one unit
26–30	Angles and geometry	Sketch, label and measure the angles using a protractor
31–35	Perimeter, area and symmetry	Draw shapes with labelled units and fold paper to test symmetry
36–40	Data, algebra and patterns	Read chart keys, substitute values, and explain the number rule

A sample six-day preparation schedule

Day 1: Numbers and whole-number operations (Questions 1–8)
Day 2: Factors, integers, fractions and decimals (Questions 9–20)
Day 3: Ratio, proportion and real-life word problems (Questions 21–25)
Day 4: Geometry and mensuration (Questions 26–35)
Day 5: Data, algebra and reasoning (Questions 36–40)
Day 6: Retry missed skills with changed numbers; discuss the underlying methods

Adjust the number of questions per session to your own learning pace. A correctly explained solution is more valuable than guessing quickly.

Frequently asked questions

Are these Class 6 Maths Olympiad questions free?

Yes. All 40 questions, options and explanations appear on this page without payment or an account.

Can I see the answers without downloading a PDF?

Yes. Every question is immediately followed by its answer and explanation. You can print the page from your browser if you prefer paper practice.

Are these questions from an official previous-year SCO examination?

No. They are original practice questions designed around Class 6 mathematics concepts. Official competition resources and rules are available on the SCO subject page.

Which topics should a Class 6 learner revise first?

Start with large numbers, operations, factors, multiples, integers, fractions and decimals. Progress to ratio, geometry, mensuration, algebra, data and patterns once you understand the basics.

Are SCO and SOF Maths Olympiads the same examination?

No. They are different organisers. See the SOF Class 6 IMO syllabus if you are preparing for that competition.

Is there a time limit for these practice questions?

No. These examples are for learning. Use a timer only after practising the concepts, and follow the chosen organiser’s actual instructions for a live examination.

Can I practise easier maths first?

Yes. Try our Class 5 maths questions with explanations for earlier concepts, then return to these Class 6 problems.

How should I review an incorrect answer?

Check each calculation or rule, solve a similar question with different numbers, and explain why the correct option works. Avoid memorising an answer letter.

Keep learning: Visit the Class 6 Maths Olympiad chapter hub for more topic-based lessons and current syllabus materials.