Powers and roots

alsergi wrote:Please help me with this!!!! Thanks in advance.

If 2^6 < x < 2^8, is x closer to 2^6 or 2^8 ?

1. x is closer to 2^4 than to 2^9
2. x is closer to 2^5 than to 2^7

IMO D

I would go for B, replacing the powers by their real value makes it easier.

B

ok so 2^6 = 64 and 2^ 8 = 256 (i calculated it out, wasnt that hard if you know 2^3 = 8 as a starting point)

now, the midpoint of this range is = (256+64)/2 = 160. so we can assume that we have to find if X is lower than 160.

Statement I

2^4 = 16 2^9 = 512
midpoint = (512+16)/2 = 264

Insufficient because X could be anywhere between 160 and 264.

Sattement II

2^5 = 32 2^7 = 128
midpoint = (128+32)/2 = 80

Sufficient because X is now definitely below 160.


Alternative explanation -

I solved this quickly at first by finding that the range was way too big in Statement I vs. Statement II, so I chose B in the end. Then I calculated the mid-points etc. to be able to post in this thread.

Would love to know if B is correct.

I think it's B too. I agree with niraj_a's explanation.

niraj_a wrote:B

ok so 2^6 = 64 and 2^ 8 = 256 (i calculated it out, wasnt that hard if you know 2^3 = 8 as a starting point)

now, the midpoint of this range is = (256+64)/2 = 160. so we can assume that we have to find if X is lower than 160.

Statement I

2^4 = 16 2^9 = 512
midpoint = (512+16)/2 = 264

Insufficient because X could be anywhere between 160 and 264.

Sattement II

2^5 = 32 2^7 = 128
midpoint = (128+32)/2 = 80

Sufficient because X is now definitely below 160.


Alternative explanation -

I solved this quickly at first by finding that the range was way too big in Statement I vs. Statement II, so I chose B in the end. Then I calculated the mid-points etc. to be able to post in this thread.

Would love to know if B is correct.

Answer should be D....

How you can take mide point of statements values....
x is unique as in stimulus...

Yes, definitely the right answer is B. Thank you all !!!!

alsergi wrote:Please help me with this!!!! Thanks in advance.

If 2^6 < x < 2^8, is x closer to 2^6 or 2^8 ?

1. x is closer to 2^4 than to 2^9
2. x is closer to 2^5 than to 2^7