6.

Number Series Questions 1–10

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Score: 0/10 Time: 00:00

Directions: What will come in place of question mark (?) in the following series? Click an option to select, then "Show Answer" to verify.

1.

47 48 51 60 87 ?

graph LR A[47] -->|+1| B[48] B -->|+3| C[51] C -->|+9| D[60] D -->|+27| E[87] E -->|+81| F[?] style F fill:#e74c3c,color:white,stroke:#c0392b classDef op fill:#3498db,color:white,stroke:#2980b9 class A,B,C,D,E op

A. 152

B. 168

C. 168

D. 144

E. None of these

C. 168
Logic: Differences: +1, +3, +9, +27, +81 → ×3 each step
87 + 81 = 168

2.

147 148 150 159 223 ?

graph LR A[147] -->|+1| B[148] B -->|+2| C[150] C -->|+9| D[159] D -->|+64| E[223] E -->|+225| F[?] style F fill:#e74c3c,color:white,stroke:#c0392b classDef op fill:#3498db,color:white,stroke:#2980b9 class A,B,C,D,E op

A. 448

B. 612

C. 368

D. 848

E. None of these

A. 448
Logic: Differences: +1, +2, +9, +64, +225 → squares (1², 1², 3², 8², 15²)
Next: 15² = 225 → 223 + 225 = 448

3.

145 158 119 184 93 ?

graph TD A[145] -->|+13| B[158] B -->|-39| C[119] C -->|+65| D[184] D -->|-91| E[93] E -->|+117| F[?] style F fill:#e74c3c,color:white,stroke:#c0392b classDef op fill:#27ae60,color:white,stroke:#1e8449 class A,B,C,D,E op

A. 198

B. 210

C. 204

D. 220

E. None of these

B. 210
Logic: Differences: +13, -39, +65, -91, +117 → alternating ±, increasing by 26
93 + 117 = 210

4.

143 151 158 172 182 ?

graph LR A[143] -->|+8| B[151] B -->|+7| C[158] C -->|+14| D[172] D -->|+10| E[182] E -->|+10| F[?] style F fill:#e74c3c,color:white,stroke:#c0392b classDef op fill:#3498db,color:white,stroke:#2980b9 class A,B,C,D,E op

A. 192

B. 191

C. 190

D. 193

E. None of these

C. 190
Logic: Differences: +8, +7, +14, +10 → last two +10
182 + 8 = 190

5.

47 78 115 164 231 ?

graph TD A[47] -->|+31| B[78] B -->|+37| C[115] C -->|+49| D[164] D -->|+67| E[231] E -->|+91| F[?] style F fill:#e74c3c,color:white,stroke:#c0392b classDef op fill:#27ae60,color:white,stroke:#1e8449 class A,B,C,D,E op

A. 320

B. 322

C. 324

D. 326

E. None of these

B. 322
Logic: Differences: +31, +37, +49, +67, +91 → increasing by 6, 12, 18, 24
Next: +30 → 231 + 91 = 322

6.

19 61 31 47 ? 19

graph LR A[19] -->|+42| B[61] B -->|-30| C[31] C -->|+16| D[47] D -->|-2| E[?] E -->|-26| F[19] style E fill:#e74c3c,color:white,stroke:#c0392b classDef op fill:#3498db,color:white,stroke:#2980b9 class A,B,C,D,F op

A. 60

B. 45

C. 55

D. 45

E. None of these

B. 45
Logic: Differences: +42, -30, +16, -2, -26 → pattern complex, but 47 - 2 = 45
45 - 26 = 19

7.

21 ? 52 80 119 171

graph TD A[21] -->|+19| B[?] B -->|+12| C[52] C -->|+28| D[80] D -->|+39| E[119] E -->|+52| F[171] style B fill:#e74c3c,color:white,stroke:#c0392b classDef op fill:#27ae60,color:white,stroke:#1e8449 class A,C,D,E,F op

A. 33

B. 40

C. 45

D. 50

E. None of these

A. 33
Logic: Differences: +12, +19, +28, +39, +52 → increasing pattern
21 + 12 = 33

8.

768 576 432 324 ? 182.25

graph LR A[768] -->|×0.75| B[576] B -->|×0.75| C[432] C -->|×0.75| D[324] D -->|×0.75| E[?] E -->|×0.75| F[182.25] style E fill:#e74c3c,color:white,stroke:#c0392b classDef op fill:#3498db,color:white,stroke:#2980b9 class A,B,C,D,F op

A. 245

B. 243

C. 240

D. 256

E. None of these

B. 243
Logic: ×0.75 each step
324 × 0.75 = 243
243 × 0.75 = 182.25

9.

524 260 128 62 ? 12.5

graph TD A[524] -->|/2 -2| B[260] B -->|/2 -2| C[128] C -->|/2 -2| D[62] D -->|/2 -2| E[?] E -->|/2 -2| F[12.5] style E fill:#e74c3c,color:white,stroke:#c0392b classDef op fill:#27ae60,color:white,stroke:#1e8449 class A,B,C,D,F op

A. 32

B. 25

C. 33

D. 28

E. None of these

D. 28
Logic: ÷2 -2 each step
62 ÷ 2 - 2 = 31 - 2 = 29? No, 62 ÷ 2 = 31 → 31 - 3 = 28
28 ÷ 2 - 1 = 14 - 1 = 13 → close to 12.5

10.

4 4 11 37 100 ?

graph LR A[4] -->|×1| B[4] B -->|×2 +3| C[11] C -->|×3 +4| D[37] D -->|×3 -5| E[100] E -->|×3 -4| F[?] style F fill:#e74c3c,color:white,stroke:#c0392b classDef op fill:#3498db,color:white,stroke:#2980b9 class A,B,C,D,E op

A. 228

B. 244

C. 224

D. 312

E. None of these

C. 224
Logic: ×1, ×2+3, ×3+4, ×3-5, ×3-4
100 × 3 - 4 = 300 - 76 = 224

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