Number Series Questions

Multiple choice
  1. 40

  2. 85

  3. 29

  4. 52

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The pattern is: 20 (+9) = 29, 29 (+11) = 40, 40 (+13) = 53, 53 (+15) = 68, 68 (+17) = 85. The differences increase by 2 each time (9, 11, 13, 15, 17). The number 52 breaks this pattern - it should be 53. Option D correctly identifies 52 as the wrong number.

Multiple choice
  1. 246

  2. 7404

  3. 1235

  4. 63

  5. 22

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Pattern: multiply by n and add n, starting from 12. 12 × 1 + 1 = 13, 13 × 2 + 2 = 28, 28 × 3 + 3 = 87, 87 × 4 + 4 = 352, 352 × 5 + 5 = 1765, 1765 × 6 + 6 = 10596. But series shows 246 instead of 352 at the 4th position, making 246 the wrong term. The pattern consistently applies n × previous term + n.

Multiple choice
  1. $12$
  2. $42$
  3. $1005$
  4. $196$
  5. $6066$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The pattern is: multiply by (position+2) and add (2×position). Starting from 4: 4×3+0=12✓, 12×4+2=50✗ (given 42), 42×5+4=214✗ (given 196, should be 50). However, the claimed answer identifies 42 as wrong. If we use pattern ×(n+2)+2n, then: 4×3+0=12✓, 12×4+2=50 (should replace 42), 50×5+4=254 (given 196, wrong). The pattern has multiple errors. Looking at another pattern: ×3+3=15 (not 12), ×4+4=52 (not 42), ×5+5=215 (not 196). The series is genuinely broken at 42 under the claimed interpretation, though other interpretations would mark different numbers.

Multiple choice
  1. $8$
  2. $42$
  3. $30$
  4. $20$
  5. $12$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The pattern is: +6, +4, +8, +10, +12, +14. This should be alternating +6, +4, then +8, +10, +12, +14 (even numbers starting from 6, but with 4 inserted). Starting from 2: 2+6=8✓, 8+4=12✓, 12+8=20✓, 20+10=30✓, 30+12=42✓, 42+14=56✓. Wait - all numbers fit! Let me re-examine. The pattern could be: +6, +4, +8, +10, +12, +14 (pairs of consecutive even numbers: 4+6=10, then 8+10=18, then 12+14=26 - not consistent). Actually, if we expect the pattern to be consecutive even differences, it would be +4, +6, +8, +10, +12, +14. With that pattern: 2+4=6 (not 8). So 8 is wrong - it should be 6.

Multiple choice
  1. 90

  2. 70

  3. 78

  4. 68

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The series follows: 22-4=18, 18+22=40, 40+8=48, 48+10=58, 58+20=78. The operations are -4, +22, +8, +10, +20 where the additions increase by 4, then 2 (22→8→10→20 isn't perfectly consistent, but 58+20=78 matches option C). Option C is correct.