Number Series Questions for CAT with Answers PDF

The series follows the pattern as given below:
+1, +2, +4, +8, +16, +32
13 + 8 = 21; 
21 + 16 = 37;
So, 26 is the wrong number.
The number should be 21 in place of 26. 

The pattern is:
4 + 13 = 5
5 + 23 = 13
13 + 33 = 40
40 + 43 = 104 ≠ 105
104 + 53 = 229
229 + 63 = 445

Here, the given series is as follows.
55 = 50 x 1 +5
115 = 55 x 2 + 5
350 = 115 x 3 + 5 ≠ 352
1405 = 350 x 4 + 5
7030 = 1450 x 5 + 5
42185 = 7030 x 6 + 5
295300 = 42185 x 7 + 5 

Therefore, this is the correct answer.

 The given series follows a pattern as shown below.
2 + 2² - 1 = 2 + 4 - 1 = 5
5 + 3² - 1 = 5 + 9 - 1 = 13
13 + 4² - 1 = 13 + 16 - 1 = 28
28 + 5² - 1 = 28 + 25 - 1 = 52
52 + 6² - 1 = 52 + 36 - 1 = 87
87 + 7² - 1 = 87 + 49 - 1 = 135
Therefore, 55 is the wrong term in the series.

 The series is as follows.
7 × 6 = 42
8 × 7 = 56
9 × 8 = 72
10 × 9 = 90
11 × 10 = 110
12 × 11 = 132
13 × 12 = 156
Therefore, option (4) is the correct answer.

Series is
25 × 5 = 125
25 × 6 = 150
25 × 7 = 175
25 × 8 = 200
25 × 9 = 225
25 × 10 = 250
Therefore, option (4) is the correct answer.

 The number series is in the pattern,
21 + (2 x 3) = 27
27 + (4 x 5) = 47
47 + (6 x 7) = 89
89 + (8 x 9) = 161
161 + (10 x 11) = 271
Thus, in the given series, the number 161 should be in the place of 160.

The number series is in the pattern,
13 x 2 + 2 = 28
28 x 2 + 2 = 58
58 x 2 + 2 = 118
118 x 2 + 2 = 238
238 x 2 + 2 = 478
Thus in the given series, the number 118 should be placed in the place of 120.

27 + (3)² = 27 + 9 = 36
36 - (4)² = 36 - 16 = 20
20 + (5)² = 20 + 25 = 45
45 - (6)² = 45 - 36 = 9
9 + (7)² = 9 + 49 = 58 = ?

The pattern is as follows:
14 x 2 = 28
28 - 8 = 20
20 x 2 = 40
40 - 8 = 32
32 x 2 = 64
64 - 8 = 56