**Mental Maths
for Class 6**

Mental Maths for
class 6 covers every type of mental maths questions for class 6 students.

Mental Maths
for Class 6 covers the following topics:

- Knowing
our numbers
- Playing
with numbers
- Whole
numbers
- Integers
- Algebra
- Algebraic
Equations
- Geometry
- HCF
and LCM
- Fractions
- Decimals
- Ratio
and proportion
- Perimeter
and area
- Data
handling

- Mental Maths for Class 1
- Mental Maths for Class 2
- Mental Maths for Class 3
- Mental Maths for Class 4
- Mental Maths for Class 5
- Mental Maths for Class 6
- Mental Maths for Class 7
- Mental Maths for Class 8

**Mental Maths
for Class 6 with Answers**

1. Find the
difference between the place values of 6 in the numbers 67,21,430 and
32,56,430.

2. Write the smallest four-digit number using the numerals 8, 0, 3
and 7.

3. Write the predecessor of the number 909,900,909 in words.

4. Find the difference between the greatest number and the
smallest number that can be formed using the digits 5, 2, 7, 3, 1, each only
once.

5. Count by ten lakhs and write two numbers from 13,59,80,123.

6. What is the remainder when 57 is divided by 5?

7. A student multiplied 4905 by 21 instead of 12. Write an
expression with brackets to show how much his answer was greater than the
correct answer.

8. Which of the given series of numbers do not start with a prime
number?

a. 1, 3, 5, 7, …..

b. 3, 6, 9, 12, …..

c. 5, 10, 15, 20, ….

d.
7, 14, 21, 28, …..

9. Which of the following are two
consecutive prime numbers that differ by 2?

a. co-primes

b. twin primes

c. composite numbers

d. co-primes and twin primes

10. Which of the following always
have only 1 as their common factor?

a. odd numbers

b. even numbers

c. composite numbers

d. prime numbers

11. Which of the following is not
a multiple of 2?

a. 22 b. 2

c. 8 d. 1

12. The sum of two odd numbers is always ______________________.

a. odd prime number

b. odd number

c. even prime number

d. even number

13. Which numbers have exactly two factors?

a. even numbers

b. prime numbers

c. composite numbers

d. odd numbers

14. A number is divisible by 12 if it is divisible by ___________.

a. 4 and 8

b. 2 and 10

c. 3 and 4

d. 3 and 9

15. To test if a number is
divisible by 3 and 9, we use the divisibility test of ___________.

a. 3 b. 6

c. 8 d. 9

16. If a number is divisible by
10, it must be divisible by ___________.

a. 3 b. 4

c. 5 d. 8

17.
Which of the following numbers can divide both, an odd number as well as an
even number?

a. 2 b. 4

c. 5 d. 6

18. Evaluate.

a. 24 + 6 ÷ 2

b. 50 – 3 × 5

19. Simplify: 35 – [5 + {28 – (16 – 5}]

20. Simplify: 8(14 – 6) + 4(2 + 5)

21. How many whole numbers lie between 10 and 20?

a. 0 b. 10

c. 11 d. 9

22. Find the product of the largest 5-digit even number and the
smallest 2-digit odd number.

23. The number that is 1000 less than 100000 is ________.

a. Ninety thousand

b. Ninety-nine thousand

c. Nine hundred ninety-nine
thousand

d. Nine thousand nine hundred

24. Each row in a classroom has 3 girls and 2 boys. There are 8
rows in that class. Write a numerical expression to show the number of students
in that class.

25. Evaluate using 1000:

a. 432 + 999

b.
900 × 125

26. Fill in the blanks.

a. There are ____________ integers
between –3 and 3.

b. The predecessor of –1 on the
number line is ____________.

c. The successor of –6 on the number line is ____________.

27. Write the next four negative integers which are greater than
–15.

28.** **Write four integers which are less than –40 but greater
than –45.

29. Fill in the blanks.

a. 4 added to –4 gives
____________.

b. –3 added to 8 gives
____________.

c. 7 added to –1 gives ____________.

30. Solve: (– 6) + (+ 3) + (– 8) + (+ 2)

31. Write the integer which is 6 more than its additive inverse.

32. Fill in the blanks.

a. (–9) – _____________ = 15

b. (–17) – _____________ = –4

c. _____________ – (–5) = + 13

33. Write the integer which is 4 less than its additive inverse.

34.** **Write two integers whose sum is 8 and difference is
also 8.

35. Write a general rule to find the following:

a. the perimeter of a square of
side *a *units

b. the perimeter of a rectangle of
sides *l *units and *b *units

c. the perimeter of a regular
hexagon of side *p *units

d. the diameter of a circle of radius *r*

36. Find the value of *a *– *b*, if *a *= –1, *b *=
1.

37. Write algebraic expressions for the following statements.

a. 8 times of *p *is
increased by 4

b. 20 decreased by *x *

c. The sum of *y *and twice
of *x *

d. *p *is reduced by thrice of *q*

38. Riya solved *x *number of sums yesterday and today she
solved 8 sums less than yesterday. How many sums did Riya solve today?

39. Seema is 15 years old. What was her age *x *years ago?

40. The product of two numbers is 72. One of them is *d*.
Find the other number.

41. If *x *= 9 and *y *= 4, find the value of 50 – 4*x
*– 9*y*.

42. The solution of the equation *x *+ 5 = 5 is
____________________.

a. 0 b. 10

c. –10 d. 5

43. The solution of the equation *x *+ 3 = 0 is
____________________.

a. 0 b. 3

c. –3 d. 2

44. Solve: 8 + 4*x* = 32

45. Solve: 1 – 5*x *+ 14*x *= 28

46. When 7 is subtracted from 3 times a number, we get 50. Find
the number.

47. Find a number such that when 12 is added to it, the number
becomes twice of itself.

48. The number of lines that can pass through one point is
____________.** **

a. one b. two

c. none d. infinite

49. The number of lines that can
pass through two points is ____________.

a. one b. two

c. none d. infinite

50. Two distinct lines meeting at
a point are called ____________ lines.

a. parallel b. intersecting

c. collinear d. coincident

51. If p ‖ q, q ‖ r, then
____________.

a. *p*, *q*, *r *coincide

b. *p *and *r *intersect

c. *p *is parallel to *r *

d. *p *is perpendicular
to *r*

52. Find the measure of the
smaller angle between the hour hand and the minute hand when the time is

a. 3 o’ clock ___________

b. 1 o’ clock ___________

c. 4 o’ clock ___________

d. 6 o’ clock ___________

53. Fill in the blanks.

a. For a given circle, the ratio
of diameter to radius is _______________.

b. If OM is the radius of a circle
and MN is a diameter, then _______________ × OM = MN.

c. There can be _______________
diameters in a circle.

d. A given chord divides the
circle into two _______________.

e. In a circle, an arc is always named using _______________
points.

54. Which of the given numbers has all different prime factors?

a. 64

b. 81

c. 105

55. Find the missing prime factor
in the following:

a. 30 = 2 × 3 × ____

b. 385 = ____ × 7 × 11

56. What is the HCF of 36 and 48?

57.** **What is the HCF of 1 and any other number?

58. Find the smallest number which is completely divisible by 4, 5
and 6.

59. Find the lowest number that is divisible by all numbers from 1
to 5.

60. Which of the given fractions is equal to 1 whole?

a. 1/6 b. 2/6

c. 4/6 d. 6/6

61. Where is 5/7 placed on a
number line?

a. before 1/7

b. after 4/7

c. before 2/7

d. after 7/7

62. Which of the following is an
equivalent fraction for 5/5?

a. 1/5 b. 5/1

c. 2/2 d. 4/6

63. Find the fraction which is not
equivalent to the others.

a. 1/3 b. 3/9

c. 4/10 d. 5/15

64. Which of the following fractions is greater than 1/5?

a. 1/6 b. 2/10

c. 3/12 d. 1/8

65. 5/7 is the same as
__________________.

a. 7 + 7 + 7 + 7 + 7

b. 3/7 + 2/7

c. (7 + 5) (7 – 5)

d. 5 + 5 + 5 + 5 + 5 + 5 + 5

66. Write the fraction 8 out of 1000, in the decimal form.

67.** **Between which two whole numbers does 3.7 lie?

68. Write 0.15 as a fraction in its simplest form.

69.** **Write three tens and eight tenths in the decimal form.

70. Identify the smallest decimal among the following:

9.099, 9.909, 9.090, 9.009

71. Which of the following decimal numbers is less than 1/5?

a. 0.2 b. 0.02

c. 0.25 d. 0.5

72. Which decimal number is the
same as 3/5?

a. 0.4 b. 0.5

c. 0.6 d. 0.7

73. If 3*x *= 5*y*, find *x *: *y*.

74. 10 : 6 is the equivalent ratio of

a. 1 : 3 b. 3 : 1

c. 3 : 5 d. 5 : 3

75. Find the value of *x *in 5 : 3 = *x *: 18.

76. Find *x*, if 15, 18, 10 and *x *are in proportion.

77. If *a *: *b *= 3 : 4; find *b *: *a*.

78. A car can travel 48 kilometres with 4 litres of petrol. How
many kilometres can the car travel with 50 litres of petrol?

79. In a clock, when the minute hand covers 35 minutes, what type
of angle does it sweep?

a. Obtuse angle

b. Right angle

c. Straight angle

d. Reflex angle

80. The angle formed between the
hands of a clock at 4 o’clock is _______.

a. acute b. right

c. right d. obtuse

81. The sum of two obtuse angles is a _______________ angle.

a. straight b. right

c. obtuse d. reflex

82. Which has more diagonals: a hexagon or a pentagon?

83. The perimeter of a regular hexagon is 78 cm. Find the length
of each side of the regular hexagon.

84. The side of a square is 15 cm. If its side is doubled, what is
its new perimeter?

85. How many bricks will be required to lay a path 150 m long and
1.6 m wide if a brick covers an area of 0.5 sq. m?

86. The floor of a room is 4 m by 3 m. What will be the cost of
carpeting it at the rate of ₹ 95 per sq. m?

87. The perimeter of a rectangle is 220 cm. If the breadth of the
rectangle is 40 cm, find its length.

88. A symbol is used to represent 15 flowers. How many such
symbols are required to represent 60 flowers?

89.** **If ◊◊◊◊◊◊◊◊ represents 64 pencils, how many pencils are
represented by ◊◊◊◊◊◊◊◊◊◊◊?

90. Which of the following statements is false for a bar graph?

a. All bars have the same width.

b. Distance between two
consecutive bars is the same.

c. The bars do not touch each
other.

d. All bars should have the same height.

**ANSWERS**

1. 59,94,000

2. 3078

3. Nine hundred
nine million nine hundred thousand nine hundred eight

4. 62964

5. 13,69,80,123 and
13,79,80,123

6. 2

7.
4905 × (21 – 12)

8. a 9. b

10. d 11. d

12. d 13. b

14. c 15. d

16. c 17. c

18. a. 27 b. 35

19. 13 20. 92

21. d 22. 1099978

23. b 24. 8(3 + 2)

25. a. 1431 b. 112500

26. a. five b. -2 c. -5

27. -14, -13, -12, -11

28. -44, -43, -42, -41

29. a. 0 b.
5 c. 6

30. -9 31. 3

32. a. -24 b.
-13 c. 8

33. -2 34. 8 and
0

35. a. 4a b. 2(l + b)

c. 6p d. 2r

36. -2

37. a. 8p + 4 b. 20 – x

c. y
+ 2x d. p – 3q

38. x – 8 39. (15
– x) years

40. 72/d 41.
-22

42. a 43. c

44. 6 45. 3

46. 19 47. 12

48. d 49. a

50. b 51. c

52. a. 90° b. 30°

c. 120° d. 180°

53. a. 2 : 1 b. 2

c. infinite d. segments

e. 3

54. c. 105

55. a. 5 b. 5

56. 12 57. 1

58. 60 59. 70

60. d 61. b

62. c 63. c

64. c 66. 0.008

67. Between 3 and 4

68. 3/20 69. 30.8

70. 9.009

71. b 72. c

73. 5 : 3 74. d

75. 30 76. 12

77. 4 : 3 78. 600 km

79. d 80. d 81. d

82. A hexagon

83. 13 cm

84. 120 cm

85. 480 bricks

86. Rs 1140

87. 70 cm

88. 4 symbols

89. 88 pencils

90. d

**Worksheets for Maths**