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
P1,P2,P3
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- eagleeye
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I am guessing the question reads what is the value of P(4).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
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.
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