Gmat_mission wrote: ↑Fri Oct 02, 2020 12:43 am
If \(a < x < b\) and \(c < y < d,\) is \(x < y ?\)
(1) \(a < c\)
(2) \(b < c\)
Answer:
B
Source: GMAT Paper Tests
Target question: Is x < y?
Given: a < x < b and c < y < d
Statement 1: a < c
This statement doesn't FEEL sufficient, so I'll TEST some values.
There are several scenarios that satisfy statement 1 (AND the given information). Here are two:
Case a: a = 1, x = 2, b = 3, c = 4, y = 5 and d = 6. In this case,
x < y
Case b: a = 1, x = 10, b = 11, c = 4, y = 5 and d = 6. In this case,
x > y
Since we cannot answer the
target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: b < c
Perfect, this information allows us to COMBINE the two given inequalities.
We get:
a < x < b < c < y < d
At this point, it is clear that
x < y
Since we can answer the
target question with certainty, statement 2 is SUFFICIENT
Answer: B
