Question 1
What will be the next number? 3, 5, 7, 11, 13, 17…….
 A 21 B 19 C 25 D 20
Arithmetic Aptitude    Series
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Question 1 Explanation:
This is a sequence of prime numbers
 Question 2
Find wrong number in series:
12, 25, 49, 99, 187, 395, 789
 A 789 B 187 C 99 D 49
Series
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Question 2 Explanation:
12*2+1 =25
25*2-1 = 49
49*2+1 = 99
395*2-1 = 789
 Question 3
Find wrong number in series:
34, 7, 37, 14, 36, 28, 43, 56
 A 14 B 36 C 28 D 56
Series
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Question 3 Explanation:
mixture of series (alternate numbers)
34+3=37,
37+3 =40...
7*2= 14
14*2= 28
28*2 =56
 Question 4
Find wrong number in series:
1, 4, 9, 16, 25, 32, 49, 64
 A 9 B 25 C 32 D 64
Series
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Question 4 Explanation:
Square of natural numbers:
12=1, 22 =4, 32=9..............82=64
 Question 5
Find wrong number in series:
2, 7, 10, 22, 18, 37, 26, 46
 A 10 B 18 C 26 D 46
Series
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Question 5 Explanation:
two alternate series:
2+8 =10
7+15=22
10+8 =18
22+15=37
37+15 = 52
so, +8, +15, +8, +15, ......
 Question 6
Find wrong number in series:
4, 12, 48, 240, 1240, 10080
 A 12 B 240 C 1240 D 10080
Series
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Question 6 Explanation:
4*3=12
12*4=48
48*5 = 240
240*6 = 1440
 Question 7
Find wrong number in series:
2, 3, 6, 0, 8, -3, 14, -6
 A 3 B 0 C 8 D 3
Series
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Question 7 Explanation:
two alternate series:
2+4 =6,
3-3 =0
6+4 =10,
0-3 =-3
10+4 =14
-3-3 =-6
 Question 8
Find wrong number in series:
1, 8, 27, 64, 81, 216, 343
 A 1 B 27 C 81 D 343
Series
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Question 8 Explanation:
cubes of natural numbers
81 is not the cube of desired number
 Question 9
Find wrong number in series:
4, 5, 7, 12, 19, 35
 A 12 B 19 C 35
Series
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Question 9 Explanation:
4+20=5
5+21=7
7+22=11
11+23=19
19+24=35
 Question 10
Find wrong number in series:
23, 29, 31, 33, 41, 43, 47
 A 29 B 33 C 41 D 47
Series
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Question 10 Explanation:
prime numbers from 23
 Question 11
Find wrong number in series:
8, 24, 12, 36, 18, 54, 26
 A 12 B 24 C 18 D 26
Series
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Question 11 Explanation:
mixture of two alternate series:
8*3=24
24/2=12
12*3=36
36/2=18
18*3=54
54/2=27
 Question 12
Find wrong number in series:
7, 26, 63, 124, 215, 342,496
 A 7 B 63 C 215 D 496
Series
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Question 12 Explanation:
(23 - 1), (33 - 1), (43 - 1), (53 - 1), (63 - 1), (73 - 1), (83 - 1) = 511
 Question 13
Find wrong number in series:
1, -6, 18, -54, 162, -486
 A 1 B -6 C 162 D -486
Series
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Question 13 Explanation:
2*(-3)=-6
-6*(-3)=18
18*(-3)=-54
-54*(-3)=162
162*(-3)=-486
 Question 14
Find wrong number in series:
2, 8, 12, 20, 30, 42, 56, 72
 A 8 B 20 C 42 D 72
Series
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Question 14 Explanation:
2+4=6, 6+6=12, 12+8=20, 20+10=30, 30+12=42, 42+14=56, 56+16=72
 Question 15
Find wrong number in series:
8, 12, 16, 27, 40.5, 60.75
 A 12 B 16 C 40.5 D 60.75
Series
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Question 15 Explanation:
(8×3)÷ 2 = 12
(12×3)÷ 2 = 18
(18×3)÷ 2 = 27
(27×3)÷ 2 = 40.5
(40.5×3)÷ 2 = 60.75
 Question 16
Find wrong number in series:
15, 25, 30, 51, 85, 90, 115
 A 30 B 51 C 85 D 115
Series
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Question 16 Explanation:
All except 51 are multiple of 5
There are 16 questions to complete.

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