# Number System Questions and Answers

## Concept of Number System

Number System Questions is used in nearly every single subject matter in maths. It to a great extent describes the significance of this subject. Number System mostly involves additional sub-topics such as HCF & LCM, factors, factorials, cyclicity, Euler number, digital root, unit digit, and more. The conception of unit digit can be well-read by assuming out the unit digits of all the sole digits ranging from 0 – 9 when elevated to definite capacities. The numbers are widely categorized into three groups for this us ### Important definitions for solving Number System Questions:

• Natural Numbers: All positive integers are called natural numbers. All counting numbers from 1 to infinity are natural numbers. N = {1, 2, 3, 4, 5, 6……..∞}
• Whole Numbers: The set of numbers that includes all natural numbers and the number zero are called whole numbers. They are also called as Non-negative integers. W = { 0,1,2,3,4,5,6,7,8,………∞}
• Integers: All numbers that do not have the decimal places in them are called integers. Z = {∞…….-3, -2, -1, 0, 1, 2, 3………∞}
• Real Numbers: All numbers that can be represented on the number line are called real numbers.
• Rational Numbers: A rational number is defined as a number of the form a/b where ‘a’ and ‘b’ are integers and b ≠ 0. The rational numbers that are not integers will have decimal values. These values can be of two types
• Irrational Numbers:  It is a number that cannot be written as a ratio.An Irrational numbers are non-terminating and non-periodic fractions.

Question 1 Time: 00:00:00
Find the L.C.M of 15, 30, 45 90

90

95

95

92

92

None of the above

None of the above

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Question 2 Time: 00:00:00
The given ratio of two numbers is 3:2. If the L.C.M of them is 30, then calculate their sum. 34

34

50

50

55

55

None of the above

None of the above

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Question 3 Time: 00:00:00
Find the L.C.M of 25, 35, and 55 1900

1900

1990

1990

1925

1925

None of the above

None of the above

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Question 4 Time: 00:00:00
Calculate the HCF of 22 and 33 11

11

12

12

15

15

None of the above

None of the above

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Question 5 Time: 00:00:00
If 20 is the HCF of two particular numbers and the other two factors of their LCM are 10 and 12, find the larger number? 220

220

210

210

240

240

None of the above

None of the above

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Question 6 Time: 00:00:00
The HCF and LCM of three specific numbers are 6, 12, 18. If one number is 24, find the next number? 55

55

54

54

67

67

None of the above

None of the above

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Question 7 Time: 00:00:00
The two specific numbers are in the ratio 6:7, if the HCF of the given numbers is 30, what will be the numbers? 160, 180

160, 180

180, 210

180, 210

200,160

200,160

None of the above

None of the above

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Question 8 Time: 00:00:00
Determine the largest length of the tape, which can measure tape of 5 cm, 7cm, and 13 cm? 1

1

7

7

13

13

None of the above

None of the above

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Question 9 Time: 00:00:00
The HCF of two numbers is 45, and their LCM is 90, if one specific number is 9, find another number? 450

450

435

435

426

426

None of the above

None of the above

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Question 10 Time: 00:00:00
Street lamps start at the interval of 5, 10, 15, 20, and 25 seconds, calculate the number in which the street lamps began together in 40 minutes? 9

9

10

10

8

8

None of the above

None of the above

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Question 11 Time: 00:00:00
If the ratio between the three numbers is 2:3:5 and their L.C.M is 180, calculate their sum? 56

56

60

60

65

65

None of the above

None of the above

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Question 12 Time: 00:00:00
Find the largest numbers that will divide 12, 60, 90 and will give a similar remainder. 6

6

5

5

7

7

None of the above

None of the above

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Question 13 Time: 00:00:00
If H.C.F and L.C.M of the two given numbers are 60 and 140 and if one number is 15, then calculate another number? 450

450

570