# Quantitative Aptitude: Number Series Set 3

### Directions: The following series are based on a specific pattern. In these series one number is wrong, find that odd one.

1. 7, 23, 57, 109, 191, 307
A) 191
B) 307
C) 109
D) 57
E) 23
Option D
Pattern:

23 â€“ 12, 33 â€“ 22, 43 â€“ 32, 53 â€“ 42, â€¦.
2. 128, 72, 96, 240, 840, 3780
A) 96
B) 72
C) 240
D) 3780
E) 840
Option B
Pattern:

112Ã—0.5, 56Ã—1.5, 84Ã—2.5, 210Ã—3.5,
3. 145, 170, 195, 224, 252, 290
A) 224
B) 170
C) 252
D) 195
E) 290
Option C
Pattern:

122+1, 132+1, 142-1, 152-1, 162+1,
4. 23, 12, 13, 21, 44, 170, 340.5
A) 12
B) 13
C) 21
D) 44
E) 170
Option E
Pattern:

11*0.5 + 0.5, 6*1 + 1, 7*1.5 + 1.5, 12*2 + 2, 26*2.5 + 2.5
5. 4, 5, 11, 39, 175, 1127, 7881
A) 1127
B) 175
C) 5
D) 11
E) 39
Option B
Pattern:

Ã—2 â€“ 3, Ã—3 â€“ 4, Ã—4 â€“ 5, Ã—5 â€“ 6, Ã—6 â€“ 7
6. 6, 9, 30, 90, 432, 2520
A) 9
B) 432
C) 90
D) 30
E) 2520
Option D
Pattern:

6Ã—2 â€“ 6/2, 9Ã—3 â€“ 9/3, 24Ã—4 â€“ 24/4, 90Ã—5 â€“ 90/5, 432Ã—6 â€“ 432/6
7. 10, 6, 14, 9, 32, 16, 80
A) 9
B) 14
C) 6
D) 32
E) 16
Option B
Pattern:

– 22, + 23, – 32, + 33, – 42,
8. 5760, 352, 40, 8, 6.5, 2.5
A) 8
B) 6.5
C) 40
D) 352
E) 2.5
Option B
Pattern:

5760/16 â€“ 16/2 = 352
352/8 â€“ 8/2 = 40
40/4 â€“ 4/2 = 8
8/2 â€“ 2/2 = 3
3/1 â€“ 1/2 = 2.5
9. 6, 9, 23, 55, 92, 151, 229
A) 151
B) 92
C) 55
D) 23
E) 229
Option C
Pattern:

10. 8, 2, 2, 4.5, 25, 112.5, 1012.5
A) 1012.5
B) 112.5
C) 4.5
D) 25
E) None of these