BTGModeratorVI wrote: ↑Sun Mar 15, 2020 12:42 pm
If 0 < a < b, is c < 0?
1) cb < ca
2) |c| > 1
Answer:
A
Source: Veritas Prep
Target question: Is c < 0?
Given: 0 < a < b
Statement 1: cb < ca
Subtract ca from both sides to get: cb - ca < 0
Factor: c(b - a) < 0
IMPORTANT: if
a < b, we can be certain that (b - a) is POSITIVE.
So, we can divide both sides of the inequality by (b - a) to get:
c < 0
PERFECT!
Since we can answer the
target question with certainty, statement 1 is SUFFICIENT
Statement 2: |c| > 1
There are several values of c that satisfy statement 2. Here are two:
Case a: c = -2, in which case
c < 0
Case b: c = 2, in which case
c > 0
Since we cannot answer the
target question with certainty, statement 2 is NOT SUFFICIENT
Answer = A
Cheers,
Brent
