IMO C.
Statement 1. X can be less the 0.5 and still make the statement true, such as x = 0.1, 80<620
Insufficient
Statement 2. X can be anywhere 0.51X to 1,1.5,2, 2.46643 etc and still make the statement true. Again Insufficient.
Taking the two statements together, X is somewhere between .51 < X < .78
nmber properties
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Source: Beat The GMAT — Data Sufficiency |
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inittowinit
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gmatboost
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Let's give it a shot without finding the exact decimal values of the fractions.
Statement 1:
800x < 620
x < 620/800
x < 62/80
x < 31/40
You should recognize that 31/40 is just a little more than 3/4.
[spoiler]This means x may or may not be between 0.5 and 0.9. Insufficient.
[/spoiler]
Statement 2:
1200x > 620
x > 620/1200
x > 62/120
x > 31/60
You should recognize that 31/60 is just a little more than 1/2.
This means x may or may not be between 0.5 and 0.9. Insufficient.
Combined:
[spoiler]0.5 < 31/60 < x < 31/40 < 0.9. Sufficient.[/spoiler]
Statement 1:
800x < 620
x < 620/800
x < 62/80
x < 31/40
You should recognize that 31/40 is just a little more than 3/4.
[spoiler]This means x may or may not be between 0.5 and 0.9. Insufficient.
[/spoiler]
Statement 2:
1200x > 620
x > 620/1200
x > 62/120
x > 31/60
You should recognize that 31/60 is just a little more than 1/2.
This means x may or may not be between 0.5 and 0.9. Insufficient.
Combined:
[spoiler]0.5 < 31/60 < x < 31/40 < 0.9. Sufficient.[/spoiler]
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GMAT Boost offers 250+ challenging GMAT Math practice questions, each with a thorough video explanation, and 100+ GMAT Math video tips, each 90 seconds or less.
It's a total of 20+ hours of expert instruction for an introductory price of just $10.
View sample questions and tips without signing up, or sign up now for full access.
Also, check out the most useful GMAT Math blog on the internet here.
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krishnasty
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IMO C
From 1,
x < .77
INSUFFICIENT
From 2,
x > .51
INSUFFICIENT
Combining both, .77>x>.51
Hence, SUFFICIENT
From 1,
x < .77
INSUFFICIENT
From 2,
x > .51
INSUFFICIENT
Combining both, .77>x>.51
Hence, SUFFICIENT
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Appreciation in thanks please!!
Appreciation in thanks please!!
