# Aptitude - Odd Man Out and Series - Discussion

Discussion Forum : Odd Man Out and Series - Find Wrong No. (Q.No. 4)
Directions to Solve
Find out the wrong number in the series.

4.
445, 221, 109, 46, 25, 11, 4
221
109
46
25
11
Explanation:

Go on subtracting 3 and dividing the result by 2 to obtain the next number.

Clearly, 46 is wrong.

Discussion:
23 comments Page 1 of 3.

Kamali said:   4 years ago
It could be cracked easily when solved from right to left.

Multiplying 2 and adding 3 to the multiplied result.

(4*2)+3 = 11.
(11*2)+3 = 25.
(25*2)+3 = 53.
(53*2)+3 = 109.
(109*2)+3 = 221.
(221*2)+3 = 445.

So, 46 is the wrong answer.
(2)

Let me explain ..

445-3=442
442/2=221

221-3=218
218/2=109

109-3=106
106/2=53

53-3=50
50/2=25

25-3=22
22/2=11

11-3=8
8/2=4

So after 109 it should be 53.. in the given series it is 46 so

Have a nice day..!

Harshita said:   3 years ago
@Dhara.

Your way of solving the question is wrong because then the given series is proved wrong.

4+7=11.
11+14=25,
25+21=46,
46+28=74,
74+35=109,
109+42=251.

Hence the given solution is correct.
(2)

Kamlesh said:   6 years ago
The general form of the series is sigmal of GI (n\2) -1 put n=445 you will get 222.5 but GI of 222.5 is 222 subtract 1 from it you will get 221 and then put 221 on the series and so on.

Apoorv said:   7 years ago
Sum every digit of every number in the series.

4 5 1 1 7 2 4. There's anyhow increase and decrease in the difference of number. Except 1 at the 4th place. Which corresponds to 46!

Satya said:   10 years ago
I had solved this problem like this.
Starting from the end.

4.
4+7=11,
11+14=25,
25+21=46,
46+28=74. So 109 is wrong.

Can anybody say whether the way is correct are not? and why?

Dhara said:   4 years ago
4.

I solved the question in this way.

4+7 = 11,
11+14 = 25,
25+21 = 46,
46+28 = 74.

So, 109 should be wrong.

I am right, Can anyone tell me?

4*2+3=11
11*2+3=25
25*2+3=53 ------------ 46 which is an wrong series.
53*2+3=109
109*2+3=221
221*2+3=445

You might can understand this.

BoB said:   9 years ago
Hi but how did you find that it must be subtracted by 3 and multied by 2, seeing the question ? can any one help please.

Lakshu said:   6 years ago
We can simply do that:

445-221 = 224
224/2 = 112

221-109=112
112/2 = 56

109-46 = 63, So 46 is the wrong answer.