Aptitude Odd Man Out and Series Find Wrong No Section 1

Directions to Solve
Find out the wrong number in the series

7, 8, 18, 57, 228, 1165, 6996

Explanation: Let the given numbers be A, B, C, D, E, F, G. Then, A, A x 1 + 1, B x 2 + 2, C x 3 + 3, D x 4 + 4, E x 5 + 5, F x 6 + 6 are the required numbers. Clearly, 228 is wrong.

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1, 1, 2, 6, 24, 96, 720

Explanation: Go on multiplying with 1, 2, 3, 4, 5, 6 to get next number. So, 96 is wrong.

445, 221, 109, 46, 25, 11, 4

Explanation: Go on subtracting 3 and dividing the result by 2 to obtain the next number. Clearly, 46 is wrong.

190, 166, 145, 128, 112, 100, 91

Explanation: Go on subtracting 24, 21, 18, 15, 12, 9 from the numbers to get the next number. 190 - 24 = 166 166 - 21 = 145 145 - 18 = 127 [Here, 128 is placed instead of 127] 127 - 15 = 112 112 - 12 = 100 ... and so on. Therefore, 128 is wrong.

19, 26, 33, 46, 59, 74, 91

Explanation: Go on adding 7, 9, 11, 13, 15, 17 respectively to obtain the next number. So, 33 is wrong. It must be 35

1, 3, 10, 21, 64, 129, 356, 777

Explanation: A x 2 + 1, B x 3 + 1, C x 2 + 1, D x 3 + 1 and so on. So, 356 is wrong.

40960, 10240, 2560, 640, 200, 40, 10

Explanation: Go on dividing by 4 to get the next number. So, 200 is wrong.

3, 7, 15, 39, 63, 127, 255, 511

Explanation: Go on multiplying 2 and adding 1 to get the next number. So, 39 is wrong.

64, 71, 80, 91, 104, 119, 135, 155

Explanation: Go on adding 7, 9, 11, 13, 15, 17, 19 respectively to obtain the next number. So, 135 is wrong.

2880, 480, 92, 24, 8, 4, 4

Explanation: Go on dividing by 6, 5, 4, 3, 2, 1 respectively to obtain the next number. Clearly, 92 is wrong.