Sequence and Series - Online Test

Q1. Direction: What should come in place of the question mark (?) in the following number series?

400, 240, 144, 86.4, 51.84, 31.104, ?
Answer : Option D
Explaination / Solution:

18.6624
400 × 0.6 = 240
240 × 0.6 = 144
144 × 0.6 = 86.4
86.4 × 0.6 = 51.84
51.84 × 0.6 = 31.104
31.104 × 0.6 = 18.6624

Q2. Direction: What will come in place of the question mark (?) in the following number series?
4, 6, 9, 13.5, 20.25, 30.375, ?
Answer : Option B
Explaination / Solution:

45.5625
4 × 1.5 = 6
6 × 1.5 = 9
9 × 1.5 = 13.5
13.5 × 1.5 = 20.25
20.25 × 1.5 = 30.375
30.75 × 1.5 = 45.5625

Q3. Direction: What will come in place of the question mark (?) in the following number series?
13, 14, 30, 93, 376, 1885, ?
Answer : Option C
Explaination / Solution:

1136
13 × 1 + 1 = 14
14 × 2 + 2 = 0
30 × 3 + 3 = 93
93 × 4 + 4 = 376
376 × 5 + 5 = 1885
1885 × 6 + 6 = 11316

Q4. Direction: What should come in place of the question mark (?) in the following number series?

9, 4.5,4.5, 6.75, 13.5, 33.75, ?
Answer : Option A
Explaination / Solution:

101.25
9 × 0.5 = 4.5
4.5 × 1 = 4.5
4.5 × 1.5 = 6.75
6.75 × 2 = 13.5
13.5 × 2.5 = 33.75
33.75 × 3 = 101.25

Q5. Direction: What will come in place of the question mark (?) in the following number series?
225, 231, 249, 287, 353, (?)
Answer : Option D
Explaination / Solution:

225, 231, 249, 287, 353, (455) 
    +6  +18  +38  +66  +102 
       +12  +20 +28  +36
            +8   +8   +8

Q6. Direction: What will come in place of the question mark (?) in the following number series?
949    189.8    ?    22.776    11.388    6.8328
Answer : Option D
Explaination / Solution:

949 *0.2 = 189.8
189.8 *0.3 = 56.94
56.94 *0.4 = 22.776
22.776 *0.5 = 11.388
11.388 *0.6 = 6.8328

Q7. Direction: What will come in place of the question mark (?) in the following number series?
25 53 163 657 3291 ?
Answer : Option E
Explaination / Solution:

25*2 + 3 = 53
53*3 + 4 = 163
163*4 + 5 = 657
657*5 + 6 = 3291
3291*6 + 7 = 19753

Q8. Direction: What will come in place of the question mark (?) in the following number series?
14    43.5    264    ?    76118
Answer : Option E
Explaination / Solution:

14*3 + 1.5 = 43.5
43.5*6 + 3 = 264
264*12 + 6 = 3174
3174*24 + 12 = 76188

Q9. Direction: What will come in place of the question mark (?) in the following number series?
120, 15, 105, 17.5, 87.5, ?
Answer : Option C
Explaination / Solution:

120/8 = 15

15*7 = 105

105/6 = 17.5

17.5*5 = 87.5

87.5/4 = 21.875

Q10. Direction: What will come in place of the question mark (?) in the following number series?
499, 622, 868, 1237, 1729, 2344, ?
Answer : Option B
Explaination / Solution:

499 + 1*123 = 622; 622 + 2*123 = 868

868 + 3*123 = 1237; 1237 + 4*123 = 1729

1729 + 5*123 = 2344; 2344 + 6*123 = 3082