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Odd Man Out Series set-1
Odd Man Out Series
· Mathematics/General Ability
200 MCQs
Showing
1–20
of 200 MCQs
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1
Find the odd man out in the series: 2, 3, 5, 7, 9, 11
Answer:
9
Step 1: Analyze the numbers given in the series: 2, 3, 5, 7, 9, 11. Step 2: Observe the mathematical properties of the numbers. 2, 3, 5, 7, and 11 are all prime numbers, meaning they are only divisible by 1 and themselves. Step 3: The number 9 is a composite number (divisible by 1, 3, and 9). Therefore, 9 is the odd man out.
2
Identify the odd one out: 12, 14, 15, 18, 20, 22
Answer:
15
Step 1: Look at the sequence of numbers: 12, 14, 15, 18, 20, 22. Step 2: Check for basic properties like even and odd. 12, 14, 18, 20, and 22 are all even numbers (divisible by 2). Step 3: The number 15 is an odd number. Thus, 15 breaks the pattern and is the odd man out.
3
Find the odd number in the series: 17, 19, 23, 27, 29, 31
Answer:
27
Step 1: Examine the numbers: 17, 19, 23, 27, 29, 31. Step 2: Check for prime numbers. 17, 19, 23, 29, and 31 are all prime numbers. Step 3: The number 27 is divisible by 3 and 9, making it a composite number. Hence, 27 is the odd one out.
4
Which number is the odd man out: 31, 37, 41, 43, 47, 49
Answer:
49
Step 1: Analyze the series: 31, 37, 41, 43, 47, 49. Step 2: Identify the common trait. The numbers 31, 37, 41, 43, and 47 are consecutive prime numbers. Step 3: The number 49 is a perfect square (7 x 7) and a composite number. Therefore, 49 is the odd man out.
5
Find the odd man out: 15, 25, 30, 34, 40, 50
Answer:
34
Step 1: Observe the given series: 15, 25, 30, 34, 40, 50. Step 2: Check for divisibility rules. The numbers 15, 25, 30, 40, and 50 all end in 0 or 5, meaning they are multiples of 5. Step 3: The number 34 is not divisible by 5, making it the odd one out.
6
Identify the odd one out: 8, 12, 16, 21, 24, 28
Answer:
21
Step 1: Analyze the sequence: 8, 12, 16, 21, 24, 28. Step 2: Check for common multiples. The numbers 8, 12, 16, 24, and 28 are all multiples of 4. Step 3: The number 21 is a multiple of 3 and 7, not 4. It is also the only odd number. Thus, 21 is the odd man out.
7
Find the odd man out in the series: 13, 17, 19, 21, 23, 29
Answer:
21
Step 1: Examine the numbers: 13, 17, 19, 21, 23, 29. Step 2: Note that 13, 17, 19, 23, and 29 are all prime numbers. Step 3: The number 21 is a composite number (3 x 7). Therefore, 21 is the odd man out.
8
Which number does not belong to the group: 10, 14, 16, 18, 23, 24, 26
Answer:
23
Step 1: Look at the series: 10, 14, 16, 18, 23, 24, 26. Step 2: Check the parity (even/odd) of the numbers. All numbers except one are even numbers. Step 3: The number 23 is an odd number (and also a prime number), making it the odd one out.
9
Find the odd man out: 41, 43, 47, 53, 61, 71, 73, 75
Answer:
75
Step 1: Analyze the sequence: 41, 43, 47, 53, 61, 71, 73, 75. Step 2: Look for prime numbers. 41, 43, 47, 53, 61, 71, and 73 are all prime numbers. Step 3: The number 75 is divisible by 3, 5, 15, and 25, making it a composite number. Hence, 75 is the odd man out.
10
Identify the odd one out in the series: 11, 13, 15, 17, 19
Answer:
15
Step 1: Review the numbers: 11, 13, 15, 17, 19. Step 2: Check for prime numbers. 11, 13, 17, and 19 are consecutive prime numbers. Step 3: The number 15 is a composite number (3 x 5). Therefore, 15 is the odd man out.
11
Find the odd man out: 4, 9, 16, 25, 36, 48
Answer:
48
Step 1: Analyze the series: 4, 9, 16, 25, 36, 48. Step 2: Recognize that the numbers 4 (2^2), 9 (3^2), 16 (4^2), 25 (5^2), and 36 (6^2) are perfect squares. Step 3: The number 48 is not a perfect square (the next should be 49). Thus, 48 is the odd man out.
12
Identify the odd one out: 1, 4, 9, 16, 20, 36, 49
Answer:
20
Step 1: Look at the sequence: 1, 4, 9, 16, 20, 36, 49. Step 2: Observe that 1, 4, 9, 16, 36, and 49 are squares of 1, 2, 3, 4, 6, and 7 respectively. Step 3: The number 20 is not a perfect square (it falls between 16 and 25). Therefore, 20 is the odd one out.
13
Find the odd man out in the series: 16, 25, 36, 72, 144, 196, 225
Answer:
72
Step 1: Examine the numbers: 16, 25, 36, 72, 144, 196, 225. Step 2: Most of these numbers are perfect squares: 4^2, 5^2, 6^2, 12^2, 14^2, 15^2. Step 3: The number 72 is not a perfect square. Hence, 72 is the odd man out.
14
Which number does not belong to the group: 121, 144, 169, 196, 225, 250
Answer:
250
Step 1: Analyze the series: 121, 144, 169, 196, 225, 250. Step 2: Recognize the squares of consecutive integers: 11^2=121, 12^2=144, 13^2=169, 14^2=196, 15^2=225. Step 3: The number 250 is not a perfect square. The next square should be 256. Therefore, 250 is the odd man out.
15
Find the odd man out: 5, 10, 17, 26, 37, 50, 64
Answer:
64
Step 1: Examine the series: 5, 10, 17, 26, 37, 50, 64. Step 2: Identify the pattern: Each number is one more than a perfect square (n^2 + 1). 2^2+1=5, 3^2+1=10, 4^2+1=17, 5^2+1=26, 6^2+1=37, 7^2+1=50. Step 3: The next number should be 8^2 + 1 = 65, but 64 is given. Thus, 64 is the odd man out.
16
Identify the odd one out: 3, 8, 15, 24, 34, 48, 63
Answer:
34
Step 1: Analyze the sequence: 3, 8, 15, 24, 34, 48, 63. Step 2: Identify the pattern: Each number is one less than a perfect square (n^2 - 1). 2^2-1=3, 3^2-1=8, 4^2-1=15, 5^2-1=24. Step 3: The next should be 6^2 - 1 = 35. Instead, 34 is given. Therefore, 34 is the odd man out.
17
Find the odd man out in the series: 2, 5, 10, 17, 26, 38, 50
Answer:
38
Step 1: Look at the numbers: 2, 5, 10, 17, 26, 38, 50. Step 2: Check for a square-based pattern. The numbers follow the form n^2 + 1: 1^2+1=2, 2^2+1=5, 3^2+1=10, 4^2+1=17, 5^2+1=26. Step 3: The next term should be 6^2 + 1 = 37, but 38 is given. Hence, 38 is the odd one out.
18
Which number is the odd man out: 100, 121, 144, 169, 196, 221
Answer:
221
Step 1: Review the series: 100, 121, 144, 169, 196, 221. Step 2: Observe that 100, 121, 144, 169, and 196 are squares of 10, 11, 12, 13, and 14 respectively. Step 3: The next square should be 15^2 = 225. Since 221 is given, it is the odd man out.
19
Find the odd man out: 225, 256, 289, 324, 361, 399
Answer:
399
Step 1: Analyze the sequence: 225, 256, 289, 324, 361, 399. Step 2: The numbers are consecutive perfect squares: 15^2=225, 16^2=256, 17^2=289, 18^2=324, 19^2=361. Step 3: The next square should be 20^2 = 400. 399 is not a perfect square, making it the odd man out.
20
Identify the odd one out in the series: 81, 100, 121, 144, 169, 196, 224
Answer:
224
Step 1: Examine the numbers: 81, 100, 121, 144, 169, 196, 224. Step 2: Notice that 81 to 196 are the perfect squares of the numbers 9 through 14. Step 3: The next square is 15^2 = 225. The number 224 is given instead, making it the odd one out.
