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Expected Number Series (Missing Number/Wrong Number) for Upcoming Competitive Exams – Download in PDF:

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Directions (Q. 1-100): In each of these questions a number series is given. In each series only one number is wrong. Find out the wrong number.

1).  50 51 47 56 42 65 29

  1. 51
  2. 47
  3. 56
  4. 42
  5. 65

2).  3 9 23 99 479 2881 20159

  1. 9
  2. 23
  3. 99
  4. 479
  5. 2881

3).  7 4 6 9 20 52.5 160.5

  1. 6
  2. 4
  3. 20
  4. 9
  5. 5

4).  1 3 6 11 20 39 70

  1. 3
  2. 39
  3. 11
  4. 20
  5. 6

5).  2 13 27 113 561 3369 23581

  1. 27
  2. 13
  3. 113
  4. 561
  5. 3369

Answer With Explanation:

1). The series is 50 + 1^2 = 51, 51 – 2^2 = 47, 47 + 3^2 = 56, 56 – 4^2 = 40, 40 + 5^2 = 65, 65 – 6^2 = 29.

Hence, there should be 40 in place of 42.

Answer is: D

2). The series is 3 × 2 + 3 = 9, 9 × 3 – 4 = 23, 23 × 4 + 5 = 97, 97 × 5 – 6 = 479, 479 × 6 + 7 = 2881, 2881 × 7 – 8 = 20159

Hence, there should be 97 in place of 99.

Answer is: C

3). The series is x0.5 + 0.5, x1 + 1, x 1.5 + 1.5, x 2 + 2, x 2.5 + 2.5, x 3 + 3…

Hence, there should be 5 in place of 6.

Answer is: A

4). The series is 1 × 2 + 1 = 3, 3 × 2 + 0 = 6, 6 × 2 – 1 = 11, 11 × 2 – 2 = 20, 20 × 2 – 3 = 37, 37 × 2 – 4 = 70.

Hence, there should be 37 in place of 39.

Answer is: B

5). The series is 2 × 2 + 7 = 11, 11 × 3 – 6 = 27, 27 × 4 + 5, = 113, 113 × 5 – 4 = 561, 561 × 6 + 3 = 3369, 3369 × 7 – 2 = 23581.

Hence, there should be 11 in place of 13.

Answer is: B

 

6). 7 16 27 40 46

  1. 7
  2. 16
  3. 27
  4. 40
  5. 46

7). 729 1331 2497 3375 4913

  1. 729
  2. 1331
  3. 3375
  4. 2497
  5. 4913

8). 80 119 166 221 223

  1. 80
  2. 119
  3. 166
  4. 192
  5. 223

9). 8 8.5 11.5 14 17

  1. 8
  2. 8.5
  3. 11.5
  4. 14
  5. 17

10). 439 778 1456 2812 5624

  1. 439
  2. 778
  3. 1456
  4. 2812
  5. 5624

Answer With Explanation:

6). The series is 5 × 1 + 2 = 7, 6 × 2 + 4 = 16, 7 × 3 + 6 = 27, 8 × 4 + 8 = 40, 9 × 5 + 10 = 55.

Hence, there should be 55 in place of 46.

Alternate Method: +9, +11, +13, +15

Answer is: E

7). The series is 9^3, 11^3, 13^3, 15^3, 17^3,

Hence, there should be 2197 in place of 2497.

Answer is: D

8). The series is 9^2 – 1, 11^2 – 2, 13^2 – 3, 15^2 – 4, 17^2 – 5,

Hence, there should be 284 in place of 223.

Answer is: E

9). The series is 8 + 1.5 = 9.5, 9.5 + 2 = 11.5, 11.5 + 2.5 = 14, 14 + 3 = 17

Hence, there should be 9.5 in place of 8.5.

Answer is: B

10). The series is +339, +678, +1356, +2712,

Hence, there should be 5524 in place of 5624.

Answer is: E

11). 17, 36, 132, 635, 3500, 21750, 153762

  1. 635
  2. 17
  3. 132
  4. 3500
  5. 36

12). 17, 20, 46, 147, 599, 3015, 18018

  1. 20
  2. 46
  3. 599
  4. 147
  5. 3015

13). 90, 135, 286, 750, 2160, 6405, 19155

  1. 90
  2. 750
  3. 6405
  4. 286
  5. 2160

14). 9, 14, 40, 129, 536, 2705, 16260

  1. 14
  2. 40
  3. 536
  4. 9
  5. 129

15). 8, 18, 64, 272, 1395, 8424, 59045

  1. 18
  2. 8
  3. 272
  4. 1395
  5. 64

Answer With Explanation:

11). The number series should be 636 in the place of 635.

The series is (17 + 1^3) × 2, (36 + 2^3) × 3, (132 + 3^3) × 4, (636 + 4^3) × 5

Answer is: a)

12). The number series should be 600 in the place of 599.

The series is ×1 + 3, ×2 + 6, ×3 + 9, ×4 + 12, ×5 + 15

Answer is: c)

13). The number series should be 285 in the place of 286.

The series is (90-45) × 3, (135-40) × 3, (285-35) × 3, (750-30) × 3, (2160-25) × 3,…

Answer is: d)

14). The number series should be 38 in the place of 40.

The series is ×1 + 5, ×2 + 10, ×3 + 15, ×4 + 20, ×5 + 25

Answer is: b)

15). The number series should be 63 in the place of 64.

The series is (8+1) × 2, (18+3) × 3, (63+5) × 4, (272+7) × 5

Answer is: e)

 

16). 32, 39, 65, 128, 253, 467, 809, 1320

  1. 39
  2. 65
  3. 253
  4. 467
  5. 32

17). 38, 49, 62, 72, 77, 91, 101

  1. 49
  2. 72
  3. 77
  4. 91
  5. 38

18).19, 22, 32, 46, 73, 108, 158

  1. 22
  2. 46
  3. 73
  4. 19
  5. 158

19). 47, 44, 45, 46, 33, 57, 3, 88

  1. 44
  2. 57
  3. 46
  4. 3
  5. 47

20). 45, 131, 228, 338, 466, 619, 800

  1. 131
  2. 466
  3. 619
  4. 45
  5. 800

Answer With Explanation:

16).The series is,.

Hence, 253 is a wrong number.

Answer: C

17).The series is,

38 = 3+8 = 11 = 38 +11 = 49

49 = 4+9 = 13 = 49 +13 = 62

62 = 6+2 = 8 = 62 + 8 = 70 ≠ 72

70 = 7+0 = 7 = 70+ 7 = 77

77 = 7+7 = 14 = 77+14 = 91

91 = 9+1 = 10 = 91+10 = 101

Hence, 72 is the wrong number.

Answer: B

18).The series is,

Hence, 46 is the wrong number

Answer: B

19). First series 47, 45, 33, 3

47-(1×2) = 45

45-(3×4) = 33

33- (5×6) = 3

Second series 44, 46, 57, 88

44 + (1×2) = 46

46 + (3×4) = 58 ≠ 57

58 + (5×6) = 88

Hence, 57 is the wrong answer.

Answer: B

20).The series is,

11, 13, 19, 23 and 29 are the prime numbers

Hence, 466 is the wrong number.

Answer: B

21). 1,    8,    66,    460,    2758,    13785,    55146

  1. 460
  2. 2758
  3. 66
  4. 8
  5. 55146

22). 56,    57,    48,    73,    24,    105,    -10

  1. 57
  2. 73
  3. 105
  4. -10
  5. 24

23). 2,    2,    13,    59,    363,    2519,    20161

  1. 13
  2. 20161
  3. 2519
  4. 59
  5. 363

24). 3,    1,    3,    0.7,    3,    0.6,    3,    0.5,    3

  1. 1
  2. 7
  3. 6
  4. 3
  5. 5

25). 2,   6,   13,   26,   54,   100,   197

  1. 26
  2. 100
  3. 54
  4. 197
  5. 13

Explanation With Answer Key:

21). 1   8   66   460   2758   13785   55146

Here 1 × 9 – 1 = 8; 8 × 8 + 2 = 66; 66 × 7 – 3 = 459;

459 × 6 + 4 = 2758; 2758 × 5 – 5 = 13785; 13785

× 4 + 6 = 55146

Answer: a)

22). 56   57   48   73   24   105   -10

Here 56 +1^2 = 57;

57 – 3^2 = 48; 48+ 5^2 = 73; 73- 7^2 = 24;

24 + 9^2 = 105; 105 -11^2 = -16

Answer: d)

23). 2   2   13   59   363   2519   20161

Here 2 × 3 – 4 = 2; 2 × 4 + 5 = 13;

13 × 5 – 6 = 59; 59 × 6 + 7 = 361;

361 × 7 – 8 = 2519; 2519 × 8 + 9 = 20161

Answer: e)

24). 3   1   3   0.7   3   0.6   3

3 × 1/3 = 1;

1 × 3 = 3;

3 × 1/4 = 0.75;

0.75 × 4 = 3;

3 × 1/5 = 0.6;

0.6 × 5 = 3;

3 × 1/6 = 0.5;

0.5 × 6 = 3.

Answer: b)

25). 2   6   13   26   54   100   197

Here 2 × 2 + 2 = 6; 6 × 2 + 1 = 13;

13 × 2 + 0 = 26; 26 × 2 – 1 = 51;

51 × 2 – 2 = 100; 100 × 2 – 3 = 197

Answer: c)

 

26). 3,   7.5,   15,   37.5,   75,   167.5,   375

  1. 5
  2. 75
  3. 5
  4. 15
  5. 5

27). 0,   1,   9,   36,   99,   225,   441

  1. 9
  2. 36
  3. 99
  4. 225
  5. 441

28). 2,   3,   5,   8,   14,   23,   41,   69

  1. 5
  2. 8
  3. 14
  4. 41
  5. 69

29). 5,   10,   17,   27,   37,   50,   65

  1. 10
  2. 17
  3. 37
  4. 27
  5. 50

30). 108,   54,   36,   18,   9,   6,   4

  1. 54
  2. 36
  3. 18
  4. 9
  5. 6

Explanation With Answer Key:

26). The series is ×2.5, ×2 alternately

Answer: a)

27). The differences are

0  1 9  36  99  225  441

02   12   32  62   102   152  212

Answer: c)

28). The series is an alternate series, having

S 1 = 2   5   14   41; ×3 – 1 in each term

S 2 = 3   8   23   69; ×3 – 1 in each term

Answer: e)

29). The series is +5, +7, +9, +11, ….

Answer: d)

30). The series is ÷2, ÷1.5 alternately.

Answer: d)

31). 4,  12,   42,  196,  1005,  6066,  42511

a) 12

b) 42

c) 196

d) 1005

e) 6066

32). 7,  13,  25,  49,  97,  194,  385

a) 13

b) 25

c) 49

d) 194

e) 385

33). 10,  15,  24,  35,  54,  75,  100

a) 10

b) 24

c) 35

d) 54

e) 100

34). 2,  8,  32,  148,  765,  4626,  32431

a) 32431

b) 765

c) 148

d) 32

e) 2

35). 73,  57,  49,  44,  43,  42

a) 73

b) 57

c) 49

d) 44

e) 42

Explanation With Answer Key:

31). b)

4, 12, 42, 196, 1005, 6066, 42511

4 × 2+(2)= 12

12× 3+(3)= 45

45× 4+(4)= 196

196× 5+(5)= 1005

1005× 6+(6)= 6066

6066× 7+(7)= 42511

Hence, 42 is the wrong number

32). d)

7, 13, 25, 49, 97, 194, 385

7×  2 -1= 13

13×  2 -1= 25

25× 2 -1= 49

49×  2 -1= 97

97× 2 -1= 193

193× 2 -1= 385

Hence, 194 is the wrong number

33). c)

10, 15, 24, 35, 54, 75, 100

Hence, 35 is the wrong number

34). d)

2, 8, 32, 148, 765, 4626, 32431

2 × 2+22= 8

3 × 8+32= 33

4 × 33+42= 148

5 × 148+52= 765

6  ×765+62= 4626

7 × 4626+72=32431

Hence, 32 is the wrong number.

35). d)

73, 57, 49, 44, 43,42

73-57= 16

57-49=8

49-45= 4

45-43= 2

43-42=1

Differences between the consecutive numbers are in Geometric Progression (G.P)

Hence, 44 is the wrong number.

 

36). 1527,    1185,    985,    865,    823,    817

a) 985

b) 865

c) 823

d) 817

e) 1185

37). 110,    106,    204,    608,    2384,    11900

a) 2384

b) 106

c) 11900

d) 608

e) 204

38). 71,    90,    128,    185,    261,    365

a) 365

b) 128

c) 185

d) 90

e) 261

39). 8,    17.5,    64.75,    157.375,    561.3125,    1400.78125

a) 5

b) 75

c) 375

d) 3125

e) 78125

40). 18,    36,    144,    864,    6912,    691020

a) 691020

b) 144

c) 864

d) 6912

e) 36

Solution With Answer Key:

36). A) The series is

1527 — (192 -19) = 1185,

1185 — (152 — 15) =975,

975— (112— 11) = 865,

865 — (72— 7) = 823,

823 — (32 — 3) = 817

There should be 975 in place of 985.

37). D) The series is 110 x 1 — 4 = 106,

106 x 2 — 8 = 204, 204 x 3 — 12 = 600, 600 x 4 — 16 = 2384, 2384 x 5 — 20 = 11900

There should be 600 in place of 608.

38). A) The series is

71 + 19 = 90, 90 + 38 = .128, 128 + 57 = 185, 185 + 76 = 261, 261 + 95 = 356 Hence there should be 356 in place of 365.

39). C) The series is

8 x 2.5 — 2.5 = 17.5,

17.5 x 3.5 + 3.5 = 64.75,

64.75 x 2.5 — 2.5 = 159.375,

159.375 x 3.5 + 3.5 = 561.3125,

561.3125 x 2.5 — 2.5 = 1400.78125, …

Hence there should be 159.375 in place of 157.375.

40). A) The series is .

Hence there should be 69120 in place of 691020

41). 76,    75,    142,    399,    1530,    7535

a) 399

b) 142

c) 75

d) 1530

e) 7535

42). 84,    138,    192,    270,    348,    434

a) 192

b) 138

c) 84

d) 348

e) 434

43). 88,    88,    176,    530,    2112,    10560

a) 88

b) 176

c) 2112

d) 105602

e) 530

44). 2400,    1295,    625,    255,    80,    15

a) 2400

b) 1295

c) 625

d) 80

e) 15

45). 45,    62,    81,    102,    123,    150

a) 45

b) 62

c) 102

d) 81

e) 123

Solution With Answer Key:

41). D) The series is

76 x 1 — 13= 75,

75 x 2 — 23 = 142,

142 x 3 — 33 = 399,

399 x 4 — 43 = 1532,

1532 x 5 — 53 = 7535, …

Hence there should be 1532 in place of 1530.

42). A) The series is

21 x 4 = 84,

23 x 6 = 138,

25 x 8= 200,

27 x 10 = 270,

29 x 12 = 348,

31 x 14 = 434, …

Hence there should be 200 in place, of 192.

Therefore the wrong number is 192.

43). E) The series is

Hence there should be 528 in .place of 530.

Therefore the wrong number is 530.

44). C) The series is 74 — 1 = 2400,

64 — 1 = 1295, 54— 1 = 624, 44 – 1 = 255, 34— 1 = 80, 24 — 1 = 15, …

Hence there should be 624 in place of 625.

Therefore, the wrong number is 625.

45). E) The series is

Hence there should be 125 in place of 123.

Therefore the wrong number is 123.

 

46). 127   470   686   811   875   885

a) 470

b) 686

c) 811

d) 885

e) 875

47). 1296   652   328   169   88.5   48.25

a) 328

b) 169

c) 5

d) 1296

e) 652

48). 2   5   15   131   530   13257

a) 5

b) 15

c) 131

d) 530

e) 13257

49). 508   640   776   925   1092   1283

a) 640

b) 508

c) 925

d) 1092

e) 1283

50). 1325   714   318  90   -18   -54

a) 714

b) 318

c) 90

d) -18

e) 1325

Solution With Answer Key:

46). The series is +73, +63, +53, +43, +33, +23, …

The series is 127 + 343 = 470, 470 + 216 = 686, 686 + 125 = 811, 811 + 64 = 875, 875 + 27 =902,

Therefore it should be 902 in place of 885.

Answer: d)

47). The series is ÷2 + 4 (repeated)

1296 ÷ 2 + 4 = 652, 652 ÷ 2 + 4 = 330, 330 ÷ 2 + 4 = 169, 169 ÷ 2 + 4 = 88.5, 88.5 ÷ 2 + 4 = 48.75, …

Therefore it should be 330 in place of 328.

Answer: a)

48). The series is 2 x 12 + 3= 5, 5 × 2 + 4 = 14, 14 x 32 + 5 = 131, 131 x 4 + 6 = 530, 530 x 52 + 7 = 13257,……

Therefore it should be 14 in place of 15.

Answer: b)

49). The series is 508 + 131 = 639, 639 + 137 = 776, 776 + 149 = 925, 925 + 167 = 1092, 1092 + 191 = 1283, …

Hence it ‘should be 639 in place of 640.

Answer: a)

50). The series is (11)3 – 5 = 1326,

(9)3 – 15 = 714, (7)3 – 25 = 318, (5)3 – 35 = 90, (3)3 – 45 = -18, (1)3 – 55 = -54

Hence it should be 1326 in place of 1325.

Answer: e)

 

51). 34/15,   76/35,   130/63,   202/99,   290/143,   394/195

a) 130/63

b) 76/35

c) 202/99

d) 290/143

e) 34/15

52). 5930,   4900,   7056,   3969,   8281,    3136

a) 4900

b) 7056

c) 5930

d) 8281

e) 3136

53). 28,  55,  83,  138,  221,  360

a) 360

b) 55

c) 138

d) 221

e) 28

54). 85,   88,  182,   550,   2232,   11175

a) 182

b) 88

c) 85

d) 550

e) 2232

55). 46,   300,   430,   494,  526,   542

a) 526

b) 300

c) 494

d) 542

e) 46

Solution With Answer Key:

51). B) The series follows:

Numerator = 2 x Denominator + 4

So, 76/35 should be replaced by (35×2+4) / 35 = 74/35

52). C) The series is (77)2, (70)2, (84)2, (63)2, (91)2, (56)2, …

5929,   4900,  7056, 3969,  8281,  3136

Hence there should be 5929 in place of 5930

53). A) The series is

Hence there should be 359 in place of 360.

54). D) The series is 85 x 1 + 3 = 88,

88 x 2 + 6 = 182, 182 x 3 + 9 = 555, 555 x 4 + 12 = 2232,  2232 x 5 + 15 = 11175,…..

Hence there should be 555 in place of 550.

55). B) Move from right to left. The series is

-16,  -32,  -64,  -128,  -256, …..

Hence there should be 302 in place of 300.

 

56). 11  12  28  93  310  1965

a) 12

b) 93

c) 1965

d) 310

e) 28

57). 3  20  87  392  2025  12246

a) 12246

b) 87

c) 392

d) 20

e) 2025

58).12  6.8  7.5  12.75  27.5  71.25

a) 5

b) 5

c) 75

d) 25

e) 8

59). 5  33  225  1345  6724  26881

a) 225

b) 6724

c) 26881

d) 33

e) 225

60). 225  256  289  344  361  400

a) 225

b) 361

c) 344

d) 256

e) 400

Solution With Answer Key:

56). D) The series is 11 x 1 + 12 = 12, 12 x 2 + 22 = 28, 28 x 3 + 32= 93, 93 x 4 + 42 = 388, 388 x 5 + 52 = 1965, …

There should be 388 in place of 310.

57). A) (3 + 7) x 2 = 20, (20 + 9) x 3 = 87,  (87 + 11) x 4 = 392, (392 + 13) x 5 = 2025, (2025 + 15) x 6 = 12240,

Therefore, there should be 12240 in place of 12246.

58). E) The series is 12 x 0.5 + 0.5 = 6.5, 6.5 x 1 + 1 = 7.5, 7.5 x 1.5 + 1.5 = 12.75, 12.75 x 2 + 2 = 27.5, 27.5 x 2.5 + 2.5 = 71.25, …

Therefore, there should be 6.5 in place of 6.8.

59). B) The series is 5 x 8 – 7 = 33, 33 x 7 – 6 = 225, 225 x 6 – 5 = 1345, 1345 x 5 – 4 = 6721, 6721 x 4 – 3 = 26881,

Therefore, there should be 6721 in place of 6724.

60). C) The series is (15)2 = 225, (16)2 =256, (17)2 = 289, (18)2 = 324, (19)2 = 361, (20)2  = 400,

Therefore there should be 324 in place of 344.

 

61). 11, 12, 26, 81, 320, 1645

a) 11

b) 12

c) 81

d) 320

e) None of these

62). 9, 26, 65, 126, 217, 342

a) 9

b) 126

c) 26

d) 342

e) None of these

63). 18, 10, 11, 17.5, 40, 91, 274

a) 18

b) 11

c) 10

d) 40

e) None of these

64). 12, 30, 99, 408, 2050, 12348

a) 12

b) 30

c) 2050

d) 408

e) None of these

65). 50, 51, 47, 56, 45, 65, 29

a) 45

b) 50

c) 29

d) 65

e) None of these

Solution With Answer Key:

61). The series is

11*1 + 1 = 12

12*2 + 2 = 26

26*3 + 3 = 81

81*4 + 4 = 328

328*5 + 5 = 1645

so 320 is wrong

Answer: d)

62). Here the number follows the given rule

23 + 1, 33 – 1 , 43 + 1, 53 – 1, 63 + 1, 73 – 1

so 126 is wrong number.

Answer: d)

63). Wrong Number: 40

Correct Number: 37

18 * 0.5 + 1 = 10

10 * 1 + 1 = 11

11 * 1.5 + 1 = 17.5

17.5 * 2 + 1 = 36

36 * 2.5 + 1 = 91

91 * 3 + 1 = 274

Answer: d)

64). (9×1) + 3 = 12

(12×2) + 6 = 30

(30×3) + 9 = 99

(99×4) + 12 = 408

(408×5) + 15 = 2055

(2055×6) + 18 = 12348

Answer: c)

65). 50 + 12 (1) = 51

51 – 22 (4) = 47

47 + 32 (9) = 56

56 – 42 (16) = 40

40 + 52 (25) = 65

65 – 62 (36) = 29

Answer: a)

 

66). 190  166  145  128  112  100   91

a) 100

b) 91

c) 128

d) 112

e) 145

67). 20480   5120   1280   320   100   20   5

a) 5120

b) 320

c) 1280

d) 100

e) 5

68). 60   67   76    87    99    115

a) 67

b) 87

c) 76

d) 115

e) 99

69). 7   8   18   57   228   1165   6996

a) 228

b) 57

c) 1165

d) 8

e) 18

70). 1   1   2   6    24    96   720

a) 720

b) 96

c) 24

d) 6

e) 2

Solution With Answer Key:

66). C)  Subtracting 24, 21, 18, 15, 12.

67). D)  Dividing previous number by 4.

68). E)  Go on adding 7, 9, 11, 13, 15, …

69). A)  The series is:

7 × 1 + 1 = 8

8 × 2 + 2 = 18

18 × 3 + 3= 57

57 × 4 + 4 = 232 not 228

232 × 5 + 5 = 1165

1165 × 6 + 6 = 6996

228 is wrong.

70). B)  The series is:

1 × 1 = 1

1 × 2 = 2

2 × 3 = 6

6 × 4 = 24

24 × 5 = 120 not 96

120 × 6= 720

96 is wrong

71). 2   12   36  81  150  252

  1. 2
  2. 81
  3. 36
  4. 150
  5. 252

72). 5  16  27  44  65   90

  1. 16
  2. 5
  3. 44
  4. 65
  5. 90

73). 4  2  0  -5  -12  -21

  1. 0
  2. 4
  3. 2
  4. -5
  5. -21

74). 101   123   149   179   218   251

  1. 251
  2. 123
  3. 179
  4. 218
  5. 101

75). 9   21   45   101   211   433  879

  1. 21
  2. 45
  3. 211
  4. 433
  5. 101

Solution With Answer Key:

71). The series is 12 x 2 = 2, 2x 3 = 12, 32 x 4 = 36, 4x 5 = 80, 52 x 6= 150, 6x 7 = 252 Hence, 81 should be replaced by 80.

Answer: b)

72). The series is 1 x (2 + 3) = 5, 2 x (3 + 4) = 14,3 x (4 + 5)=27,4 x(5 +6)=44,5 x(6 + 7)=65,6 x(7 + 8) = 90.

Hence, 16 should be replaced by 14.

Answer: a)

73). The series is 32 – 2-1= 4,

42 – 3 – 2= 3,

5– 4– 32= 0;

62 – 5– 4= -5;

7– 6 – 5= 12,

8– 7– 62 = -21. Hence, 2 should be replaced by 3.

Answer: c)

74). The series is 102+ 1+ 0= 101,

11+1+1=123,

12 + 1+2= 149,

13+1+3=179,

14+1+4=213,

15+ 1 + 5 =251

Hence, 218 should be replaced by 213.

Answer: d)

75). Theseriesis x2+3,  x2+5,  x2+7,  x2+9,  x2+11…

Hence, 45 should be replaced by 47.

Answer: b)

 

76). 2   11   38   197   1172   8227   65806

  1. 11
  2. 38
  3. 197
  4. 1172
  5. 8227

77). 16   19   21   30   46   71   107

  1. 19
  2. 21
  3. 30
  4. 46
  5. 71

78). 7   9   16   25   41   68   107   173

  1. 107
  2. 16
  3. 41
  4. 68
  5. 25

79). 4   2   3.5   7.5    26.25   118.125

  1. 125
  2. 25
  3. 5
  4. 2
  5. 5

80). 16   4   2   1.5    1.75   1.875

  1. 875
  2. 75
  3. 5
  4. 2
  5. 4

Solution With Answer Key:

76). The series is based on the following pattern:

11 = 2 × 3 + 5

38 = 11 × 4 – 6

197 = 38 × 5 + 7

1172 ≠ 197 × 6 – 8

1172 is wrong and it should be replaced by 197 × 6 – 8 = 1174

Answer: d)

77). The series is based on the following pattern:

107 – 71 = 36 = 62

71 – 46 = 25 = 52

46 – 30 = 16 = 42

30 – 21 = 9 = 32

21 – 19 = 2 ≠ 22

19 I should be replaced by 17 for which 21 – 17 = 22

Answer: a)

78). The series is based on the following pattern:

16 = 9 + 7

25 = 16  + 9

41 = 25 + 16

68 ≠ 41 + 25

Answer: d)

79). The series is based on the following pattern:

Obviously, 3.5 is the wrong number which should be replaced by 3.

Answer: c)

80). The series is based on the following pattern:

Obviously, 1.75 is the wrong number which should be replaced by 1.5.

Answer: b)

 

81). 7   4    6    9    20    52.5     160.5

  1. 6
  2. 4
  3. 20
  4. 9
  5. 5

82). 4   6   12   30   75    315    1260

  1. 315
  2. 75
  3. 12
  4. 6
  5. 30

83).  3   4   13   38   87    166     289

  1. 38
  2. 13
  3. 87
  4. 166
  5. 4

84).  4   5   9   29    111    556    3335

  1. 5
  2. 9
  3. 29
  4. 111
  5. 556

85). 2   6   16   38   84    176    368

  1. 6
  2. 16
  3. 38
  4. 84
  5. 176

Solution With Answer Key:

81). A) ×1/2+1/2, ×1+1, ×1(1/2)+1(1/2)…..

82).B)  ×1(1/2), ×2, ×2(1/2),…

83).D)  +12, +32, +52, ….

84).C)  ×1+1, ×2-1, ×3+1, ×4-1….

85).E) ×2+2, ×2+4, ×2+6,…

 

86). 2   3   6   18   109    1944     209952

  1. 3
  2. 6
  3. 18
  4. 109
  5. 1944

87). 1   3   6   11   20  39   70

  1. 3
  2. 39
  3. 11
  4. 20
  5. 6

88). 2   13   27   113    561   3369    23581

  1. 13
  2. 27
  3. 113
  4. 561
  5. 3369

89). 50   51    47    56   42    65   29

  1. 51
  2. 47
  3. 56
  4. 42
  5. 65

90). 3   9    23    99   479    2881    20159

  1. 9
  2. 23
  3. 99
  4. 479
  5. 2881

Solutions

86).D)  2×3=6; 3×6=18; 6×18=108; 18×108=1944….

87).B)  1×2+1=3; 3×2+0=6; 6×2-1=11; 11×2-2=20; 20×2-3=37….

88).A) 2×2+7=11; 11×3-6=27; 27×4+5=113; 113×5-4=561……

89).D)  50+12= 51; 51-22=47; 47+32=56;56-42=40;…

90).C)  3×2 +3 =9 ; 9×3-4 =23; 23×4+5 =97; 97×5-6=479…

91). 22, 37, 52, 67, 84, 97

  1. 52
  2. 84
  3. 97
  4. 67
  5. None of these

92). 11, 42, 39, 164, 525, 421, 749

  1. 164
  2. 421
  3. 525
  4. 749
  5. None of these

93). 10, 41, 94, 1624, 2516, 3625, 4936

  1. 1624
  2. 2516
  3. 3625
  4. 4936
  5. None of these

94). 4, 7, 13, 25, 49, 97, 153

  1. 25
  2. 49
  3. 97
  4. 153
  5. None of these

95). 1  3  10  36  152  760  4632

  1. 3
  2. 36
  3. 4632
  4. 760
  5. None of these

Solutions With Answer Key:

91). The pattern is as follows

So, 84 is the incorrect term, it should be 82.

Answer: b)

92). In rest of the numbers, one digit is the square of the rest part of the number.

Answer: b)

93). The pattern is as follows

10 = (1)2 (0)2,  41 = (2)2 (1)2,  94 = (3)2 (2)2 ,  2516 = (5)2(4)2 ,  3625 = (6)2(5)2

4936 = (7)2(6)2 ,  but in 1624 it is not so.

Answer: d)

94). The pattern is as follows

So, 153 is the wrong term in the series

Answer: d)

95). The pattern is as follows

From above, we can say that 760 is wrong in the given series. 770 should come in place of 760.

 

96). 729 1331 2497 3375 4913

  1. 729
  2. 1331
  3. 3375
  4. 2497
  5. 4913

97). 8  8.5  11.5  14  17

  1. 8
  2. 5
  3. 5
  4. 14
  5. 17

98). 7  16  27  40  46

  1. 7
  2. 16
  3. 27
  4. 40
  5. 46

99). 439  778  1456  2812  5624

  1. 439
  2. 778
  3. 1456
  4. 2812
  5. 5624

100). 80  119  166  221  223

  1. 80
  2. 119
  3. 166
  4. 192
  5. 223

Solutions With Answer Key:

96). The series is 93, 113, 133, 153, 173, …

Hence, there should be 2197 in place of 2497.

Answer: d)

97). The series is 8 + 1.5 = 9.5, 9.5 + 2

= 11.5, 11.5 + 2.5 = 14, 14 + 3 = 17

Hence, there should be 9.5 in place of 8.5.

Answer: b)

98). The series is 5 × 1 + 2 = 7, 6 × 2 + 4 =

16, 7 × 3 + 6 = 27, 8 × 4 + 8 = 40, 9 × 5 + 10

= 55. Hence, there should be 55 in place of 46.

Alternate Method: +9, +11, +13, +15 …

Answer: e)

99). The series is +339, +678, +1356, +2712, …

Hence, there should be 5524 in place of 5624.

Answer: e)

100). The series is 92 – 1, 112 – 2, 132 – 3, 152 – 4, 172 – 5, …

Hence, there should be 284 in place of 223.

Answer: e)

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