If wx=y, what is the value of xy?
(1) wx² = 16
(2) y = 4
Statement 1: wx² = 16
Test TWO CASES.
If the value of xy is the SAME in each case, then the statement is SUFFICIENT.
If the value of xy CHANGES, then the statement is INSUFFICIENT.
Case 1: w=4 and x=2, so that wx² = 4*2² = 16
Here:
y = wx = 4*2 = 8.
xy = 2*8 = 16.
Case 2: w=16 and x=1, so that wx² = 16*1² = 16.
Here:
y = wx = 16*1 = 16.
xy = 1*16 = 16.
Since the value of xy is the same in each case, SUFFICIENT.
Statement 2: y=4
No way to determine the value of x.
INSUFFICIENT.
The correct answer is
A.
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