Find Wrong No.

Go on multiplying the number by 2 and adding 1 to it to get the next number.

So, 27 is wrong.

Go on adding 7, 9, 11, 13, 15, 17, 19 respectively to obtain the next number.

So, 135 is wrong.

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.

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.

Go on adding 7, 9, 11, 13, 15, 17 respectively to obtain the next number.

So, 33 is wrong. It must be 35

Go on multiplying 2 and adding 1 to get the next number.

So, 39 is wrong.

Each even term of the series is obtained by multiplying the previous term by 2.

2^nd term = (1^st term) x 2 = 6 x 2 = 12

4th term = (3^rd term) x 2 = 48 x 2 = 96.

6^th term = (5^th term) x 2 = 384 x 2 =768.

Therefore 4^th term should be 96 instead of 100.

Go on dividing by 4 to get the next number.

So, 200 is wrong.

A x 2 + 1, B x 3 + 1, C x 2 + 1, D x 3 + 1 and so on.

So, 356 is wrong.

2^nd term = (1^st term) x 3 - 4 = 10 x 3 - 4 = 26.

3^rd term = (2^nd term) x 3 - 4 = 26 x 3 - 4 = 74.

4^th term = (3^th term) x 3 - 4 = 74 x 3 - 4 = 218.

5^th term = (4^th term) x 3 - 4 = 218 x 3 - 4 = 650.

5^th term must be 650 instead of 654.