The Number System is a important topic for quantitative section and 3 to 4 question asked in the examination. The Number System is a Mathematical value that contains a number and symbols. As the name suggests Number Series are numbers in some pattern or sequence. Number series can either be missing or wrong and candidates either need to find the wrong or the missing number. In this article we are discussing the Number Series topics Quantitative section 10 Practice Questions with Detailed Solutions and a few tips and tricks as to how to solve such questions. candidates bookmark our article and check start their number system preparation with practical questions and their solutions.
Different Types of Questions Asked in Number Series
Question 1: The following numbers form a series. Find the odd one out.
80, 60, 20, 10, 5, 2.5
A) 80
B) 60
C) 20
D) 10
E) 5
Ans: 2
Solution:
80/2 = 40
40/2 = 20
20/2 = 10
10/2 = 5
5/2 = 2.5
Therefore, 40 should be in place of 60.
Hence, option b.
Question 2: The following numbers form a series. Find the odd one out.
86, 83, 77, 64, 41, -7
A) 64
B) 77
C) 86
D) 83
E) 41
Ans: 1
Solution:
86 – 3 = 83
83 – 6 = 77
77 – 12 = 65
65 – 24 = 41
41 – 48 = -7
Therefore, 65 should be in place of 64.
Hence, option a.
Question 3: The following numbers form a series. Find the odd one out.
9, 10, 14, 23, 40, 64
A) 9
B) 10
C) 14
D) 23
E) None of these
Ans: 5
Solution:
9 + 12 = 9 + 1 = 10
10 + 22 = 10 + 4 = 14
14 + 32 = 14 + 9 = 23
23 + 42 = 23 + 16 = 39
39 + 52 = 39 + 25 = 64
Therefore, 39 should be in place of 40.
Hence, option e.
Question 4: The following numbers form a series. Find the odd one out.
3, 5, 8, 12, 17, 24
A) 8
B) 12
C) 24
D) 5
E) 17
Ans: 3
Solution:
3 + 2 = 5
5 + 3 = 8
8 + 4 = 12
12 + 5 = 17
17 + 6 = 23
Therefore, 23 should be in place of 24.
Hence, option c.
Question 5: The following numbers form a series. Find the odd one out.
1, 3, 7, 15, 30, 63
A) 30
B) 3
C) 7
D) 63
E) 15
Ans: 1
Solution:
1 × 2 + 1 = 3
3 × 2 + 1 = 7
7 × 2 + 1 = 15
15 × 2 + 1 = 31
31 × 2 + 1 = 63
Therefore, 31 should be in place of 30.
Hence, option a.
Question 6: What will come in place of the question mark (?) in the following series?
23, 38, 68, 113, ?, 248
A) 151
B) 162
C) 173
D) 184
E) 155
Ans: 3
Solution:
The series follows the pattern:
23 + 15 × 1 = 38,
38 + 15 × 2 = 68,
68 + 15 × 3 = 113,
113 + 15 × 4 = 173,
173 + 15 × 5 = 248.
Hence, option c.
Question 7: What will come in place of the question mark (?) in the following series?
250, 249, 241, 214, ?, 25
A) 164
B) 150
C) 188
D) 172
E) None of these
Ans: 2
Solution:
The series follows the pattern:
250 – 13 = 249,
249 – 23 = 241,
241 – 33 = 214,
214 – 43 = 150,
150 – 53 = 25.
Hence, option b.
Question 8: What will come in place of the question mark (?) in the following series?
140, 150, 170, 210, 290, ?
A) 510
B) 380
C) 540
D) 430
E) 450
Ans: 5
Solution:
The series follows the pattern:
140 + 10 = 150,
150 + 20 = 170,
170 + 40 = 210,
210 + 80 = 290,
290 + 160 = 450.
Hence, option e.
Question 9: What will come in place of the question mark (?) in the following series?
472.5, ?, 105, 60 ,40 , 32
A) 210
B) 240
C) 250
D) 265
E) None of these
Ans: 1
Solution:
The series follows the pattern:
472.5 / 2.25 = 210,
210 / 2 = 105,
105 / 1.75 = 60,
60 / 1.5 = 40,
40 / 1.25 = 32.
Hence, option a.
Question 10: What will come in place of the question mark (?) in the following series?
33, 34, 70, 213, 856, ?
A) 3245
B) 3664
C) 4285
D) 4675
E) 4854
Ans: 3
Solution:The series follows the pattern:
33 × 1 + 1 = 34,
34 × 2 + 2 = 70,
70 × 3 + 3 = 213,
213 × 4 + 4 = 856,
856 × 5 + 5 = 4285.
Hence, option c.
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The number system is a writing system for expressing numbers using digits or symbols in a consistent manner. The most common number system is the decimal system, which is based on ten digits (0-9).
The primary types of number systems are the decimal (base 10), binary (base 2), octal (base 8), and hexadecimal (base 16) systems.
Natural numbers are positive integers starting from 1 and increasing without end (1, 2, 3, …).
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