Number Series Questions

Multiple choice
  1. 71

  2. 41

  3. 34.5

  4. 21

  5. 180

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

The series follows the pattern: multiply by an increasing factor (0.5, 1, 1.5, 2, 2.5) and add 0.5. Starting from 41: 41 × 0.5 + 0.5 = 21, 21 × 1 + 0.5 = 21.5 (not 21), 21.5 × 1.5 + 0.5 = 32.75... The second 21 breaks this pattern. If we follow the pattern correctly: 41 → 21 → 31.5 → 47.5 → 71 → 106, so 21 is incorrect.

Multiple choice
  1. 1175

  2. 932

  3. 763

  4. 642

  5. 561

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

The pattern in the number series is that each term is obtained by adding the square of consecutive odd numbers: 561 + 9² = 561 + 81 = 642; 642 + 11² = 642 + 121 = 763; 763 + 13² = 763 + 169 = 932; 932 + 15² = 932 + 225 = 1157; 1157 + 17² = 1157 + 289 = 1446. The term 1175 breaks this pattern - it should be 1157.

Multiple choice
  1. 5

  2. 73

  3. 315

  4. 1

  5. 1621

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

Analyzing the pattern: 5 = 4×1 + 1, 19 = 4×5 - 1, 73 = 4×19 - 3. The pattern appears to be: multiply previous term by 4, then subtract consecutive odd numbers (1, 3, 5, 7, ...). Following this pattern: 73×4 - 5 = 292 - 5 = 287. However, the series shows 315, which breaks the pattern. The correct number after 73 should be 287, making 315 the wrong number in the series.

Multiple choice
  1. 120

  2. 10

  3. 3420

  4. 1660

  5. 770

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

The series follows the pattern n² + (n+2)² for n = 1, 5, 9, 13, 17: 1+9=10, 25+49=74 (should be 120), 81+121=202 (should be 340), 169+225=394 (should be 770), 289+361=650 (should be 1660). The term 770 should be 772 following the pattern of differences 110, 220, 440, 880, making 770 the wrong number.

Multiple choice
  1. 12

  2. 42

  3. 196

  4. 1005

  5. 6066

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

Number series pattern: n×(n+1)+n. 4×2+2=10 (should be 12), 12×3+3=39 (should be 42), 42×4+4=172 (should be 196). After 196, pattern changes to n×(n+5)-n: 196×9-9=1755 (not 1005), 1005×11-11=11044 (not 6066). Multiple terms deviate from the pattern. 42 is marked as wrong but 50×3+3=153 (not 42). The pattern is inconsistent.

Multiple choice
  1. $152$
  2. $132$
  3. $144$
  4. $162$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The differences between consecutive terms are: 22-14=8, 37-22=15, 61-37=24, 96-61=35. These differences themselves follow a pattern: 15-8=7, 24-15=9, 35-24=11. So next difference should be 35+13=48, making 96+48=144. The second-level differences increase by 2 each time (7, 9, 11, 13).

Multiple choice
  1. The first bracket number (from left) is correct and the second is false.

  2. Both parentheses are incorrect numbers.

  3. Both parentheses are correct numbers.

  4. The first bracket number (from left) is incorrect and the second is correct.

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

Odd-positioned numbers (4, 10, 16, 22) increase by 6 each. Even-positioned numbers should also increase by 6: 6, 12, 18. So the first bracket (12) is correct, but the second bracket (14) is incorrect.