4, 6, 8, 9, 10, 11, 12

Subtract 1, 3, 5, 7, 9, 11 from successive numbers.

So, 34 is wrong.

1, 1 + 1² = 2, 2 + 2² = 6, 6 + 3² = 15, 15 + 4² = 31, 31 + 5² = 56, 56 + 6² = 92

Last number of given series must be 92 not 91.

The numbers are 1 ³, 2 ³, 3 ³, 4 ³ etc. So, 124 is wrong; it must have been 5 ³ i.e., 125.

Go on adding 5, 8, 11, 14, 17, 20.

So, the number 47 is wrong and must be replaced by 46.

Each of the number except 279 is a multiple of 11.

Subtract 20, 25, 30, 35, 40, 45 from successive numbers.

So, 0 is wrong.

Terms at odd places are 5, 6, 7, 8 etc. and each term at even place is 16.

So, 9 is wrong.

Prime numbers 2, 3, 5, 7, 11, 13 are to be added successively.

So, 165 is wrong.

The terms are successively divided by 12, 10, 8, 6, ...etc.

So, 24 is wrong, it should be 8 (48/6 = 8).

The differences between two successive terms from the beginning are 7, 5, 7, 5, 7, 5.

So, 40 is wrong.