gmat_winter wrote:Is the number x between 0.1 and 1.0?
(1) 420x is less than 168.
(2) 650x is greater than 130.
OAC
Target question: Is x between 0.1 and 1.0?
Statement 1: 420x is less than 168.
So, 420x < 168
Divide both sides by 420 to get: x < 168/420
Simplify to get: x < 0.4
There are several values of x that satisfy this condition. Here are two:
Case a: x = 0.2, in which case
x IS between 0.1 and 1
Case b: x = -5, in which case
x is NOT between 0.1 and 1
Since we cannot answer the
target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: 650x is greater than 130.
So, 650x < 130
Divide both sides by 650 to get: x > 130/650
Simplify to get: x > 0.2
There are several values of x that satisfy this condition. Here are two:
Case a: x = 0.3, in which case
x IS between 0.1 and 1
Case b: x = 5, in which case
x is NOT between 0.1 and 1
Since we cannot answer the
target question with certainty, statement 2 is NOT SUFFICIENT
Statements 1 and 2 combined
Statement 1 says that x < 0.4
Statement 2 says that x > 0.2. In other words, 0.2 < x
Combine to get 0.2 < x < 0.4
If x is between 0.2 and 0.4, then we can be certain that
x is between 0.1 and 1
Since we can answer the
target question with certainty, the combined statements are SUFFICIENT
Answer =
C
Cheers,
Brent
