# Series Set – 18

1. 375, 75, 30, 18, ?, 14.4
A) 15
B) 15.2
C) 16
D) 14.4
E) 16.5

Option D
Pattern:
Here last value is in decimals
So there is a possibility that the numbers are multiplied or divided by some decimal quantity
× 0.2, × 0.4, × 0.6, × 0.8, × 1.0

2. 25, 89, 332, 588, 713, ?
A) 855
B) 856
C) 749
D) 860
E) 785

Option C
Pattern:
When the number increase suddenly, we use multiplication to find pattern. But here they are not increasing suddenly, so try addition/subtraction
25 + 26, 89 + 35, 332 + 44, 588 + 53, 713 + 62

3. 18, 36, 62, 96, 138, ?
A) 172
B) 206
C) 244
D) 220
E) 188

Option E
Pattern:
18 + 18 = 36
36 + (18+8) = 36 + 26 = 62
62 + (26+8) = 62 + 34 = 96
96 + (34+8) = 96 + 42 = 138
138 + (42+8) = 188

4. 16, 24, 60, 210, 945, ?
A) 5197.5
B) 4234.5
C) 5848.5
D) 4113.5
E) 5434.5

Option A
Pattern:
16×1.5, 24×2.5, 60×3.5, 210×4.5, 945×5.5

5. 8, 18, 86, 308, 828, ?
A) 1955
B) 1902
C) 1406
D) 1838
E) 1629

Option D
Pattern:
8 + (2^3 + 2) = 18,
18 + (4^3 + 4) = 86,
86 + (6^3 + 6) = 308,
308 + (8^3 + 8) = 828,
828 + (10^3 + 10) = 1838

6. 16, 20, 28, 27, 42, ?
A) 26
B) 45
C) 67
D) 42
E) 32

Option E
Pattern:
16………. 20……….. 28…………. 27………. 42……….. 32
.     +4          +8              -1             +15          -10
.          +22            -32            +42            -52

7. 5, 7, 11, 37, ?, 721
A) 143
B) 294
C) 138
D) 147
E) 256

Option A
Pattern:
5*1 + 2, 7*2 – 3, 11*3 + 4, 37*4 – 5, 143*5 + 6

8. 21, 33, 85, 301, 1359, ?
A) 6066
B) 7359
C) 7480
D) 6242
E) 5155

Option C
Pattern:
×1.5 + 1.5, ×2.5 + 2.5,  ×3.5 + 3.5,  ×4.5 + 4.5, ×5.5 + 5.5,

9. 6, 9, 24, 90, 432, ?
A) 2380
B) 1340
C) 2460
D) 2520
E) 1420

Option D
Pattern:
6×2 – 6/2 = 9,
9×3 – 9/3 = 24,
24×4 – 24/4 = 90,
90×5 – 90/5 = 432,
432×6 – 432/6 = 2520

10. 4, 13, 41, 126, ?, 1151
A) 382
B) 688
C) 453
D) 562
E) 436