x-4=z
y-x=8
8-z=t
For the system of equations given, what is the value of z?
(1) x = 7
(2) t = 5
OA: D
Hello. Anyone, please share the solution on how to solve this. Thanks.
OG2015 DS x-4=z
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- lionsshare
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Target question: What is the value of z?lionsshare wrote: i) x - 4 = z
ii) y - x = 8
iii) 8 - z = t
For the system of equations given, what is the value of z?
(1) x = 7
(2) t = 5
Statement 1: x = 7
Scanning the three given equations, we see that equation i is all we need to determine the value of z
i) x - 4 = z
Replace x with 7 to get: 7 - 4 = z
So, z = 3
Since we can answer the target question with certainty, statement 1 is SUFFICIENT
Statement 2: t = 5
Scanning the three given equations, we see that equation iii is all we need to determine the value of z
iii) 8 - z = t
Replace t with 5 to get: 8 - z = 5
So, z = 3
Since we can answer the target question with certainty, statement 2 is SUFFICIENT
Answer: D
Cheers,
Brent
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- Jeff@TargetTestPrep
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Your Answer
A
B
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D
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Global Stats
We are given 3 equations:lionsshare wrote:x-4=z
y-x=8
8-z=t
For the system of equations given, what is the value of z?
(1) x = 7
(2) t = 5
1) x - 4 = z
2) y - x = 8
3) 8 - z = t
We need to determine the value of z.
Statement One Alone:
x = 7
We see that we can substitute 7 for x in the first equation and then determine the value of z.
x - 4 = z
7 - 4 = z
3 = z
Statement one alone is sufficient to answer the question.
Statement Two Alone:
t = 5
We see that we can substitute 5 for t in equation 3 and then determine the value of z.
8 - z = t
8 - z = 5
3 = z
Statement two alone is sufficient to answer the question.
Answer: D
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