Number Series: Spot Wrong Number in the Series

Directions (1-5): In the following number series one number is wrong. Find out the wrong number.

Ques 1. 

11, 28, 79, 231, 691, 2068

1. 79

2. 28

3. 691

4. 231

5. 2068

Ques 2. 

141, 157, 120, 185, 85, 229

1. 120

2. 85

3. 157

4. 185

5. 229

Ques 3. 

168, 195, 224, 255, 289, 323

1. 168

2. 224

3. 289

4. 323

5. 255

Ques 4.

Ques 5. 

34, 85, 153, 187, 214, 238

1. 187

2. 214

3. 34

4. 153

5. 85

Answer :

1. 4;

The series is: 

11 x 3 - 5 = 28

28 x 3 - 5 = 79

79 x 3 - 5 = 232 ≠ 231

232 x 3 - 5 = 691

691 x 3 - 5 = 2068

Hence, there should be 232 in place of 231

2. 1;

The series is : 

141 + 4² = 157

157 - 6² = 121 ≠ 120

121 + 8² = 185

185 - 10² = 85

85 + 12² = 229

Hence, there should be 121 in place of 120

3. 3;

The series is :

13² - 1 = 168, 14² - 1 = 195, 15² - 1 = 224

16² - 1 = 255 , 17² - 1 = 288 ≠ 289, 18² - 1 = 323

Hence, there should be 288 in place of 289

4. 2;

The series is:

5. 2; 

All the numbers in the series are multiple of 17 except 2014.