Data Sufficiency. We need to know if either $x$ or $y$ is even. Statement (1): $x$ is prime. $x$ could be 2 (making $xy$ even) or 3 (making $xy$ depend on $y$). Not sufficient. Statement (2): $y$ is odd. We don't know if $x$ is even or odd. Not sufficient. Combined: If $x=2$ (prime) and $y=3$ (odd), $xy=6$ (Even). If $x=3$ (prime) and $y=3$ (odd), $xy=9$ (Odd). Since we can get both Even and Odd, the answer is Not Sufficient .
To reduce traffic congestion, the city council has proposed converting a four-lane highway into a two-lane highway with dedicated bike lanes. Critics argue that this will actually increase congestion because it reduces the road capacity for cars. The city council counters that the plan will reduce congestion because it encourages residents to commute by bicycle rather than by car. prep gmat
If $2x - 5 = 5x + 4$, then $x =$ ? (A) -3 (B) -1 (C) 1 (D) 3 (E) 5 Data Sufficiency
Here’s the truth most people won’t tell you: $x$ could be 2 (making $xy$ even) or