If s/t = 2, then the value of which of the following can be determined?
I. 2t/s
II. (s - t)/t
III. (s - 1)/(t - 1)
A. I only
B. III only
C. I and II only
D. II and III only
E. I, II, and III
OA C
Source: Official Guide
If s/t = 2, then the value of which of the following can be
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BTGmoderatorDC wrote:If s/t = 2, then the value of which of the following can be determined?
I. 2t/s
II. (s - t)/t
III. (s - 1)/(t - 1)
A. I only
B. III only
C. I and II only
D. II and III only
E. I, II, and III
Given S=2t
In any options , if the denominator is equal to 0, that options cannot be determined.
In I, 2t/s , S cannot be 0 m if s/t =2. So this can be determined.
In II, s-t/t , t cannot be 0 if s/t =2. So this can also be determined
Now, In III , s-1/t-1 , denominator t-1 can be 0 if s/t=2 (s=2, t=1) So this cannot be determined.
Hence Answer is C, I and II can be determined.
OA C
Source: Official Guide
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I. 2t/sBTGmoderatorDC wrote:If s/t = 2, then the value of which of the following can be determined?
I. 2t/s
II. (s - t)/t
III. (s - 1)/(t - 1)
A. I only
B. III only
C. I and II only
D. II and III only
E. I, II, and III
If s/t = 2, then t/s = 1/2
So, 2t/s = 2(t/s) = (2)(1/2) = 1
So we CAN determine the value of 2t/s
II. (s - t)/t
Here, we can use a nice fraction property that says: (a - b)/c = a/c - b/c
We get: (s - t)/t = s/t - t/t = s/t - 1 = 2 - 1 = 1
So we CAN determine the value of (s - t)/t
III. (s - 1)/(t - 1)
Notice that, if s/t = 2, it COULD be the case that s = 2 and t = 1
When we plug these values into the expression we get: (s - 1)/(t - 1) = (2 - 1)/(1 - 1) = 1/0, which is undefined.
So we CANNOT determine the value of (s - 1)/(t - 1)
Answer: C
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Brent
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Since s = 2t, we can substitute 2t for s in each expression:BTGmoderatorDC wrote:If s/t = 2, then the value of which of the following can be determined?
I. 2t/s
II. (s - t)/t
III. (s - 1)/(t - 1)
A. I only
B. III only
C. I and II only
D. II and III only
E. I, II, and III
OA C
Source: Official Guide
I. 2t / 2t = 1
I is correct.
II. (2t - t) / t = 1
II is correct.
III. (2t -1) / (t - 1)
We see that different values of t will yield a different value of the expression, so III is not correct.
Answer: C
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