P is positive int, what is P? 1. p divided by 7 R is 4 2.

Question

P is positive int, what is P?
1. p divided by 7 R is 4
2. p^2 divided by 7 R is 2

thanks in advance for your solutions

sdanquah · Answer

P is positive int, what is P? 
1. p divided by 7 R is 4 
2. p^2 divided by R is 2 


1. not sufficient, Because all the following when divided by 7 leaves a remainder of 4, 11, 18, 25, 32 

2. Not sufficient: because 11^2 = 121, when divided by 7 leaves a remainder of 2. So is 18^2, and 25^2

Combining the two does not help us pick any single number and so I would vote for E

hardworker_indian · Answer

I think either the Q is wrong or I am hungry.

Stem: P is postive integer

I: p = 28R, Insuff have
II: p^2 = 2R, Insuff
Together, p = 28(p^2/2), p = 1/14, which does not go with the stem. 
If this is a complete question, then I choose E.

kr8 · Answer

sorry about confusion

q is

P is a +ve integer
1. P divided by 7 has a remainder of 4
2. p sqaure divided by 7 has a remainder of 2

I chose C for the following reason
1. p could be 4, 11, 18, ......
2. p^2 could be 9 or 16 etc.... 

now if p^2 = 16 then p = 4
p = 4 has a remainder of 4 when divided by 7. 

is this right?

hardworker_indian · Answer

I. P can take 4, 11, 18, 25, ...
II. P^2 can take 9, 16, 100...
Together. 4
C.

But not sure of if we would another find a number deep down..

Anonymous · Answer

Go down the line and you will find that p can be 11, 25 etc too because 11/ 7 leaves a remainder of 4 and 121/7 leaves a remainder of 2, so is 25. That means it got to be E.

sdanquah

amernassar · Answer

it is just simple


take p=4 we have

p  (4)  divided by 7 gives remainder of 4
p^2  (16)  divided by 7 gives remainder of 2


take p=11 we have

p  (11)  divided by 7 gives remainder of 4
p^2  (121)  divided by 7 gives remainder of 2

if equaton one and 2 are satisfied we get at least 2 values of p (4,11,...)
so C is not an option. answer is  E

keyV · Answer

1) p/7 gives remainder of 4 means p = 7n+4 where n is some integer
2) p^2/7 gives remainder of 2 means p^2 = 7m+2 where m is sme integer

Clearly A, B are not the answer because n,m can be anything.

Now square 1) => p^2 = (7n+4)^2 = 49n^2 + 56n + 16 = 
7(7n^2 + 8n + 2) + 2 which is of the form 7m +2.

Clearly any n in 1) will also satisfy 2) ie 2) does not provide us any more info that what 1) already does.

Therefore cannot solve without more info. Answer E

P is positive int, what is P? 1. p divided by 7 R is 4 2.

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