Logical Reasoning - Number Series - Discussion

The series is : 14 28 20 40 32 64

14+6=20
20+12=32
32+24=56

28+12=40
40+24=64

Each time the number doubles
i.e first we add 6
Then double of 6 i.e 12
After that we double 12 i.e 24..
In this way, we can get the answer.

14+14=28.
28-8=20.
20+20=40.
40-8=32.
32+32=64.
64-8=56.

We can also do it this way

14, 28 consider this as first set where the second number is twice as first number

20, 40 consider this as second set where the second number is twice as first number

32, 64 consider this as third set where the second number is twice as first number

Take the first number of each set 14, 20, 32 as A, B, C where B is A+6, C is B+12, so D would be C+24 and E would be D+48 and so on..

So, the next set would be 56, 112 and next to that would be 104, 208 and so on

14+6=20
20+(6*2)=32
32+(12*2)=56

Like this:

28+12=40
40+(12*2)=64
64+(24*2)=112

The 2 nos as one set 14, 28 , 20, 40, 32, 64..

So it can be divided as (7x2),(7x4),(10x2),(10x4),(16x2),(16x4)..

So now 7, 10, 16 fall a line.
And

7+3 = 10
10+6 (3x2)=16
16+12(6x2)=28

(or)  

7+3 (3x1) = 10
10+6(3x2) =16
16+9(3x3) =25

So the series may be either,

7, 10, 16, 28
or
7, 10, 16, 25

If we take the first series then we will get 28x2 = 56.

If we take the next series then we will get 25x2 = 50.

Both answers are correct but as we have only 56 as option here 56 is the right answer.

14*2 = 28.
28-8 = 20.
20*2 = 40.
40-8 = 32.
32*2 = 64.
64-8 = 56 easy method.

14*2 = 28,28-8 = 20;
20*2 = 40,40-8 = 32;
32*2 = 64,64-8 = 56;

Answer is 56.

Why we subtract? Its simple multiplication in sequence.
14*2 = 28.
20*2 = 40.
32*2 = 64.
64*2 = 128.

Answer 128.

Why can't we say the Answer D.

As it was Multiplied by 2 with each number and with last 64*2 can get 128.

Look at the alternate series 14, 28, 20, 40, 32, 64

14-20 = -6 28-40 = 12.
20-32 = -12(Double of above) 40-64 = 24(Double of above).

So,
32-? =Double of above i.e. 12+12 = 24.

Answer is 32+24 = 56.