NUMBER SERIES:
Number series is a crucial topic in reasoning and aptitude tests. It involves finding a pattern among a given sequence of numbers and predicting the next number(s) in the series. Number series questions can be found in various entrance exams for higher studies.
In this article, we will discuss the different types of number series, tips to solve them, and some examples to understand the concept better.
Types of Number Series:
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Arithmetic Series: In an arithmetic series, the difference between consecutive terms remains constant. For example, 2, 4, 6, 8, 10 is an arithmetic series with a common difference of 2.
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Geometric Series: In a geometric series, each term is the product of the previous term and a fixed constant. For example, 2, 6, 18, 54, 162 is a geometric series with a common ratio of 3.
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Mixed Series: A mixed series is a combination of arithmetic and geometric series. For example, 1, 3, 7, 14, 24 is a mixed series as the difference between consecutive terms is not constant, but the pattern can still be observed.
Tips to solve Number Series:
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Observe the pattern: The first step in solving a number series is to observe the pattern among the given numbers. Look for common differences, ratios, or any other arithmetic operations.
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Look for alternate patterns: Sometimes, a number series may have two or more patterns alternatively. In such cases, it is important to identify each pattern and solve the series accordingly.
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Check the options: If you are unsure of the pattern or unable to find it, check the options provided and try to eliminate the ones that do not follow the pattern.
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Practice: Regular practice is the key to solving number series questions quickly and accurately. Try to solve as many questions as possible to improve your skills.
Example problems:
1) 2, 4, 7, 11, 16, ?
Solution: The pattern in this series is as follows:
Add 2 to the first term to get the second term: 2 + 2 = 4
Add 3 to the second term to get the third term: 4 + 3 = 7
Add 4 to the third term to get the fourth term: 7 + 4 = 11
Add 5 to the fourth term to get the fifth term: 11 + 5 = 16
Add 6 to the fifth term to get the sixth term: 16 + 6 = 22
Therefore, the next number in the series is 22.
2) 3, 9, 15, 21, ?
Solution: The pattern in this series is as follows:
Add 6 to the first term to get the second term: 3 + 6 = 9
Add 6 to the second term to get the third term: 9 + 6 = 15
Add 6 to the third term to get the fourth term: 15 + 6 = 21
Add 6 to the fourth term to get the fifth term: 21 + 6 = 27
Therefore, the next number in the series is 27.
EXERCISE-1
1) 1 , 3 , 7 , 15 , 31 , ?
a) 53
b) 55
c) 63
d) 62
Ans: C
2) 14 , 58 , 234 , ? 3754.
a) 882
b) 938
c) 912
d) 1022
Ans: B
3) 11 , 33 , 55 , 77 , ?
a) 121
b) 101
c) 88
d) 99
Ans: D
4) 3 , 6 , 8 , 16 , 18 , ?
a) 36
b) 24
c) 54
d) 28
Ans: A
5) 81 , 9 , 64 , 8 , ? , 12.
a) 97
b) 96
c) 144
d) 100
Ans: C
EXERCISE-2
1) 2 , 6 , 12 , 20 , 30 , ?
a) 36
b) 40
c) 44
d) 42
Ans: D
2) 5 , 3 , 8 , 11 , ? , 30.
a) 19
b) 13
c) 17
d) 38
Ans: A
3) 4 , 3 , 12 , 9 , 2 , 18 , 3 , ? , 21.
a) 5
b) 4
c) 7
d) 3
Ans: C
4) 4 , 9 , 16 , 25 , ?
a) 30
b) 36
c) 32
d) none
5) 8 , 27 , ? , 125 , 216.
a) 16
b) 64
c) 36
d) 30
