AJWILL wrote:A series of positive number P1,P2,P3....Pn. Pn+1=Pn/3 for all values of n>=1 what is the value of 2P4 ?

P2=1/3
P2-P3=2/9

Dont know what to draw out of statement 2

OA-D

I am guessing the question reads what is the value of P(4).

We are told that P(n+1) = P(n)/3. So each successive value is 1/3 of the previous. If we know any P*(n) value, we will have the whole series.
With this in mind, let's look at the statements:

P2=1/3
Clearly this is sufficient based on our reasoning above.

P2-P3=2/9
Interesting.
We know that P(3) = P(2)/3.
So we can find P(2)using the equation in statement 2. Then it becomes the same as statement A. Sufficient again.

D is correct.