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prachi18oct
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Is rst ≤ 1?
(1) rs + rt = 5
(2) r + st = 2
A)Statement (1) ALONE is sufficient, but statement (2) is not sufficient.
B)Statement (2) ALONE is sufficient, but statement (1) is not sufficient.
C)BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D)EACH statement ALONE is sufficient.
E)Statements (1) and (2) TOGETHER are NOT sufficient.
I got this one right. But the solution mentioned was not precise. So to validate my reasoning, I am putting this up here.
From (1), there can be many combinations which will lead to different answer.
r(s+t) = 5
r = 1 ; s = 3 ; t = 2 => rst > 1
r = -1 ; s = -3 ; t = -2 => rst < 1 INSUFFICIENT
From (2), r +st = 2
Picking various numbers, we can see that the product rst will never be > 1
r = 1 ; st = 1 ( s = 5; t = 1/5) rst =1 YES
r = -3 ; st = 5 ( s = 25 ; t = 1/5) rst < 1 YES
r = 5/2 ; st = -1/2 => rst < 0 YES
SUFFICIENT.
Please suggest alternaye solutions
(1) rs + rt = 5
(2) r + st = 2
A)Statement (1) ALONE is sufficient, but statement (2) is not sufficient.
B)Statement (2) ALONE is sufficient, but statement (1) is not sufficient.
C)BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D)EACH statement ALONE is sufficient.
E)Statements (1) and (2) TOGETHER are NOT sufficient.
I got this one right. But the solution mentioned was not precise. So to validate my reasoning, I am putting this up here.
From (1), there can be many combinations which will lead to different answer.
r(s+t) = 5
r = 1 ; s = 3 ; t = 2 => rst > 1
r = -1 ; s = -3 ; t = -2 => rst < 1 INSUFFICIENT
From (2), r +st = 2
Picking various numbers, we can see that the product rst will never be > 1
r = 1 ; st = 1 ( s = 5; t = 1/5) rst =1 YES
r = -3 ; st = 5 ( s = 25 ; t = 1/5) rst < 1 YES
r = 5/2 ; st = -1/2 => rst < 0 YES
SUFFICIENT.
Please suggest alternaye solutions
