Bunuel wrote:
Is x and y are positive integers, what is the value of x?
(1) 4x - 3y = 6
(2) 3x + 5y = 22
Given: x and y are positive integers Target question: What is the value of x? Statement 1: 4x - 3y = 6 There are several values of integer x and y that satisfy statement 1. Here are two:
Case a: x = 3 and y = 2. In this case, the answer to the target question is
x = 3Case b: x = 6 and y = 6. In this case, the answer to the target question is
x = 6Since we can’t answer the
target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: 3x + 5y = 22In most circumstances, a linear equation like 3x + 5y = 22 will have infinitely many solutions. However, when we restrict the variables (x and y are
POSITIVE INTEGERS), we don't necessarily have infinitely many solutions anymore.
When we restrict x and y to positive integers, there's only one solution to this equation: x = 4 and y = 2
So, the answer to the target question is
x=4Since we can answer the
target question with certainty, statement 2 is SUFFICIENT
Answer: B
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