CBSE Class 3 Mathematics IMO Olympiad MCQs with Answers Set O

1. Simplify: 765 + 65 + 70 – 45 – 35
(a) 820
(b) 870
(c) 780
(d) 990
Answer : (a) 765 + 65 + 70 – 45 – 35
= 830 + 70 – 45 – 35
= 900 – 45 – 35
= 855 – 35
= 820.

2. Fill in the blank with appropriate number from the options given below.
5 × 300 = (5 × ◻) × 100
(a) 1
(b) 10
(c) 3
(d) 4
Answer : (c) 5 × 300 = 1500
(5 × 3) × 100 = 15 × 100 = 1500

3. 5/7 of 49 is .
(a) 35
(b) 36
(c) 46
(d) 47
Answer : (a) 5/7 of 49 = 5/7 x 49 = 35

4. Division of two digit smallest number by smallest even number is?
(a) 10
(b) 5
(c) 20
(d) 40
Answer : (b) Two digit smallest number = 10
Smallest even number = 2
Division = 10/2
Quotient = 5

5. Find the fraction of unshaded part of the given figure?

(a) 4/7
(b) 5/8
(c) 3/8
(d) 3/7
Answer : (c) Total parts = 8
Unshaded part = 3
Fraction = 3/8

6. What is the difference between the face and place value of 5 in the number, 45632?
(a) 4995
(b) 4985
(c) 4975
(d) 4945
Answer : (a) Given number = 45,632
Face value of 5 = 5
Place value of 5 = 5,000
difference = 5000 – 5 = 4995.

7. The expanded form of the number 55432 is:
(a) 50000 + 5400 + 432
(b) 50000 + 5000 + 400 + 30 + 2
(c) 50000 + 5000 + 4000 + 32
(d) 8 + 7 + 6 + 0 + 5
Answer :

expanded form of 55432 = 50000 + 5000 + 400 + 30 + 2.

8. Which of the following is a line?

Answer : (b) Line extends in both directions without end.

9. How many metres are there in 5 km 60 m?
(a) 5600 m
(b) 5800 m
(c) 5060 m
(d) 5900 m
Answer : (c) Q 1 kilometre = 1000 metres
∴ 5 km 60 m = 5 × 1000 + 60 m
= 5060 m.

10. Peter bought a bag for ₹145.75 and an instrument for ₹23.25. How much money did he pay ?
(a) ₹ 170
(b) ₹ 169
(c) ₹ 159
(d) ₹ 149
Answer : (b) Cost of a bag = ₹ 145.75
Cost of an instrument = ₹ 23.25
Total money paid by peter = ₹ (145.75 + 23.25) = ₹169.00.

11. Total rotation of second hand of a watch in 30 minutes is:
(a) 30
(b) 40
(c) 20
(d) 17
Answer : (a) Q Rotation of second hand of a watch in 1 minute = 1
∴ Rotation of second hand of a watch in 30 minutes = 1 × 30 = 30

12. The cost of 19 pens is ₹247. Find the cost of 30 such pens.
(a) ₹ 380
(b) ₹ 370
(c) ₹ 390
(d) ₹ 320
Answer : (c) Q The cost of 19 pens = ₹ 247
∴ The cost of 1 pen = 247/19 = ₹13
∴ The cost of 30 pens
= ₹ 13 × 30 = ₹ 390

13. Solve : 2735 + 5237 – 3756
(a) 7972
(b) 4216
(c) 2729
(d) 3175
Answer : (b) 2735 + 5237 – 3756
= 7972 – 3756
= 4216

14. A plane figure has four vertices and four equal sides. Which one of the following is the name of the figure?
(a) Square
(b) Equilateral triangle
(c) Parallelogram
(d) Pentagon
Answer : (a) A square has four vertices and four equal sides.

15. Replace the question mark with a number given in the options below, 56 + 47 – 23 = 89 + 5 – ?
(a) 19
(b) 18
(c) 14
(d) 10
Answer : (c) Given, 56 + 47 – 23 = 89 + 5 – ?
103 – 23 = 89 + 5 – ?
80 = 94 – ?
Subtracting 14 from 94, we get 80.

16. A figure does not have height, width and length, if it has a place then which one of the following is the name of the figure ?
(a) A point
(b) A line segment
(c) A line
(d) A ray
Answer : (a) A point does not have height, width and length but it has a place.

17. Convert, 734 centimetres in millimetres.
(a) 7340
(b) 73.40
(c) 0.7340
(d) All of these
Answer : (a) 1 centimetre = 10 millimetres
∴ 734 centimetres = 734 × 10
= 7340 millimetres.

18. Priya ate 2/5 of a pizza. What fraction of the pizza is left?
(a) 2/5
(b) 3/5
(c) 3
(d) 2
Answer : (b) Total parts of pizza = 5
Parts eaten by Priya = 2
Parts left = 3
∴ Fraction of the pizza left = 3/5

19. Match the columns. 
Column-I                           Column-II
(A) 45 kilometres      (1) 45000 millilitres
(B) 45 litre               (2) 4500 centimetre
(C) 45 metre            (3) 45000 grams
(D) 45 kilograms       (4) 45000 metres 
     A   B   C   D 
(a) 4   2   1   3
(b) 3   1   2   4
(c) 4   1   2   3
(d) 3   2   1   4
Answer : (c) (A) → 4, (B) →1, (C) → 2, (D) → 3

20. Smriti bought 3m 5 cm ribbon of red colour and 2 m 13 cm ribbon of blue colour. What is the total length of ribbons?
(a) 1 m 8 cm
(b) 8 m 15 cm
(c) 5 m 63 cm
(d) 5 m 18 cm
Answer : (d) Length of red ribbon = 3m 5 cm
Length of blue ribbon = 2m 13cm
Total length of ribbons =

21. The sum of place value and face value of digit 6 in the number 4786239 is:
(a) 60,060
(b) 6239
(c) 6006
(d) 6200
Answer :

Place value of digit 6 is 6000.
Face value of 6 is 6
∴ sum = 6000 + 6 = 6006

22. Consider the following two statements:
Statement 1: Sum of digits of a number is its expanded form.
Statement 2: Sum of place value of every digit of a number is the expanded form of that number.
Which one of the following is correct about the above statements?
(a) Statement 1 is false and 2 is true
(b) Statement 1 is true and 2 is false
(c) Both statement 1 and 2 are false
(d) Both statements 1 and 2 are true
Answer : (a) Sum of place value of digits of a number is its expanded form.

23. A line with fixed length is called line segment then a figure which has a starting point and extends in one direction is called:
(a) Ray
(b) Point
(c) Line
(d) All of these
Answer : (a) Figure which has a starting point and extends in one direction is called ray.

24. Which of the following is a closed figure?

Answer : (a)

25. Consider the following statements.
Statement 1 : We can compare 23 litre and 52 kilograms.
Statement 2 : All the faces of a cube are squares.
Now, which of the following is correct about the statements.
(a) Statement 1 is true and 2 is false.
(b) Statement 1 is false and 2 is true.
(c) Both statements 1 and 2 are true.
(d) Both statements 1 and 2 are false.
Answer : (b) We cannot compare as litre is a unit of volume and kilogram is a unit of weight.

26. Which of the following are like fractions.
(a) 1/3 and 3/4
(b) 1/4 and 4/7
(c) 2/7 and 3/7
(d) 7/2 and 2/3
Answer : (c) 2/7 and 3/7 have same denominator.

27. The cost of 4 pens is ₹ 67. What is the cost of 5 such pens?
(a) ₹ 83.75
(b) ₹ 82
(c) ₹ 80
(d) ₹ 75.80
Answer : (a) Cost of 4 pens = ₹ 64
∴ Cost of 1 pen = 67/4
∴ Cost of 5 pens 
= 67/4 x 5 = ₹ 83.75.

28. The cost of one notebook is ₹13.25.
How much money did the Miriam pay to the shopkeeper for 9 note books?
(a) ₹ 122.25
(b) ₹ 119.25
(c) ₹ 130
(d) ₹ 141.25
Answer : (b) Cost of 1 note book = ₹13.25
Cost of 9 note books
= 9 × 13.25 = ₹ 119.25

29. Cost of 6 balloons is ₹ 9 and cost of 9 kites is ₹12. How much Cody pay to the shopkeeper for 2 balloons and 3 kites?
(a) ₹7
(b) ₹ 4
(c) ₹ 8
(d) ₹ 3
Answer : (a) Cost of 6 balloons = ₹ 9
∴ Cost of 1 balloon = ₹ 9/6
∴ Cost of 2 balloons
= 9/6 x 2  = ₹ 3
Again,
Cost of 9 kites = `₹12
∴ Cost of 1 kite = ₹ 12/9
∴ Cost of 3 kites = 12/9 x 3 = ₹ 4
Total money paid to the
shopkeeper = ₹ 3 + ₹ 4 = ₹ 7.

30. What comes next in the pattern?

Answer : (b)

31. How many triangles are there in the figure below?

(a) 3
(b) 8
(c) 4
(d) 6
Answer : (b) There are 8 triangles in the given figure.

32. The shaded part of the given figure is represented by which one of the following fractions ?

(a) 3/8
(b) 7/8
(c) 9/8
(d) 1/8
Answer : (a) The figure is divided into 8 equal parts.
Fraction for shaded part = 3/8

33. There are 40 questions in a question paper if 30 questions carry 2 marks each and remaining 10 questions carry 4 marks each, then the maximum marks is:
(a) 50
(b) 80
(c) 100
(d) 90
Answer : (c) Total questions = 40
Marks for questions carry 2 marks = 30 × 2 = 60
Marks for questions carry 4 marks = 10 × 4 = 40
Total marks = 60 + 40 = 100 marks

34. What comes next?
BCD, DEF, FGH, HIJ, ........
(a) KLM
(b) LMN
(c) JKL
(d) KLM
Answer : (c) JKL

35. Which fraction is odd one out?
3/9, 2/6, 8/10, 4/12
(a) 3/9
(b) 2/6
(c) 8/10
(d) 4/12
Answer : (c) 3/9 = 1/3, 2/6 = 1/3, 4/12 = 1/3
But 8/10 = 4/5

36. David’s football game starts at 10:00 am and ends at 2:25 pm. How long does David’s game last?
(a) 2 hours twenty five minutes
(b) Three hour twenty five minutes
(c) Four hour twenty five minutes
(d) Four hour thirty five minutes
Answer : (c) If David’s game starts at 10:00 am in the morning, then by 2:25 pm, he would have played for four hour twenty five minutes.

37. How many mugs of water with capacity 500 ml are needed to fill a 5 litre bucket?
(a) 7
(b) 10
(c) 8
(d) 9
Answer : (b) Capacity of mug = 500 ml
Capacity of bucket = 5l
= 5000 ml
Number of mugs needed
= 5000 ¸ 500 = 10

38. Ritu ate 3/7 and Priya ate 2/7 of the sweets. How much sweets did they eat altogether?
(a) 6/7
(b) 5/7
(c) 1/7
(d) 4/7
Answer : (b) Ritu ate sweets = 3/7
Priya ate sweets = 2/7
They ate together = 3/7 + 2/7 = 5/7

DIRECTIONS (Qs. 39 & 40): Mr. Bee collected some flowers to make a bouquet. He made a list of flower is used in the bouquet as given below :

39. How many Roses he used ?
(a) 6
(b) 7
(c) 8
(d) 9
Answer : (c) 

40. Which flower was used the most times ?
(a) Rose
(b) Sunflower
(c) Lily
(d) Daisy
Answer : (c) Since, Lily was used the most times i.e. 12 times.