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505-555 Level|   Algebra|      
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sidmaken
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Is st = t ? (1) s = st (2) t = ts 07 Jun 2014, 13:04
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75% (00:56) correct 25% (01:10) wrong based on 899 sessions

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Is st = t ?

(1) s = st

(2) t = ts
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Bunuel
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Is st = t ? (1) s = st (2) t = ts 07 Jun 2014, 13:13
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Is st = t ?

Is \(st = t\)? --> is \(s=1\) or \(t=0\) (or both)?

(1) s = st --> \(s=0\) or \(t=1\) (or both). Not sufficient.

(2) t = ts. Directly answers the question. Sufficient.

Answer: B.
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Is st = t ? (1) s = st (2) t = ts 09 Jun 2014, 02:02
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Is st = t ?

Is \(st = t\)? --> is \(s=1\) or \(t=0\) (or both)?

(1) s = st --> \(s=0\) or \(t=1\) (or both). Not sufficient.

(2) t = ts. Directly answers the question. Sufficient.

Answer: B.

Hi Bunuel,

from st (1) : we know that 's' not equals 1 or 't' not equals 0 or both , so is this st not sufficient alone.

Pls clarify

Consider this:
If \(s=0\) and \(t\neq{0}\) (\(s = st\)), then \(st\neq{t}\). Or if \(t=1\) and \(s\neq{1}\) (\(s = st\)), then \(st\neq{t}\). So, for these cases the answer to the question is NO.

If \(s=t=0\) (\(s = st\)), then \(st={t}\). Or if \(s=t=1\) (\(s = st\)), then \(st={t}\). So, for these cases the answer to the question is YES.

Does this make sense?
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Is st = t ? (1) s = st (2) t = ts 08 Jun 2014, 22:48
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Bunuel
Is st = t ?

Is \(st = t\)? --> is \(s=1\) or \(t=0\) (or both)?

(1) s = st --> \(s=0\) or \(t=1\) (or both). Not sufficient.

(2) t = ts. Directly answers the question. Sufficient.

Answer: B.

Hi Bunuel,

from st (1) : we know that 's' not equals 1 or 't' not equals 0 or both , so is this st not sufficient alone.

Pls clarify
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Is st = t ? (1) s = st (2) t = ts 09 Jun 2014, 10:12
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Quote:
Consider this:
If \(s=0\) and \(t\neq{0}\) (\(s = st\)), then \(st\neq{t}\). Or if \(t=1\) and \(s\neq{1}\) (\(s = st\)), then \(st\neq{t}\). So, for these cases the answer to the question is NO.

If \(s=t=0\) (\(s = st\)), then \(st={t}\). Or if \(s=t=1\) (\(s = st\)), then \(st={t}\). So, for these cases the answer to the question is YES.

Does this make sense?


Yes Bunuel, when we consider values it makes sense.
But I am unable to get to this directly with out plugging values.
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Is st = t ? (1) s = st (2) t = ts 10 Jun 2017, 08:13
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Bunuel
Is st = t ?

Is \(st = t\)? --> is \(s=1\) or \(t=0\) (or both)?

(1) s = st --> \(s=0\) or \(t=1\) (or both). Not sufficient.

(2) t = ts. Directly answers the question. Sufficient.

Answer: B.


For (1)

could be also assume following cases ?

case 1: s=t=0 then s=st

case 2: s=5,t=1 then s≠st

thanks =)
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Is st = t ? (1) s = st (2) t = ts 08 Dec 2017, 11:02
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Bunuel
Is st = t ?

Is \(st = t\)? --> is \(s=1\) or \(t=0\) (or both)?

(1) s = st --> \(s=0\) or \(t=1\) (or both). Not sufficient.

(2) t = ts. Directly answers the question. Sufficient.

Answer: B.
@bunnel If we have a statement that restates the question , then it becomes insufficient as we don't have any additional information to answer the question. But here the equality nullifies it and directly answers the question. Hence it is sufficient. IS this reasoning correct ?
i
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Is st = t ? (1) s = st (2) t = ts 08 Dec 2017, 11:09
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Raksat
Bunuel
Is st = t ?

Is \(st = t\)? --> is \(s=1\) or \(t=0\) (or both)?

(1) s = st --> \(s=0\) or \(t=1\) (or both). Not sufficient.

(2) t = ts. Directly answers the question. Sufficient.

Answer: B.
@bunnel If we have a statement that restates the question , then it becomes insufficient as we don't have any additional information to answer the question. But here the equality nullifies it and directly answers the question. Hence it is sufficient. IS this reasoning correct ?
i

Not sure I can follow you.

Say the question asks: is x = 1? And (1) says that x = 1. In this case (1) is sufficient as it directly answers the question: YES x does equal to 1. This is EXACTLY the case we have with the above question.
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Is st = t ? (1) s = st (2) t = ts 08 Dec 2017, 11:54
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Raksat
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Is st = t ?

Is \(st = t\)? --> is \(s=1\) or \(t=0\) (or both)?

(1) s = st --> \(s=0\) or \(t=1\) (or both). Not sufficient.

(2) t = ts. Directly answers the question. Sufficient.

Answer: B.
@bunnel If we have a statement that restates the question , then it becomes insufficient as we don't have any additional information to answer the question. But here the equality nullifies it and directly answers the question. Hence it is sufficient. IS this reasoning correct ?
i

Not sure I can follow you.


Say the question asks: is x = 1? And (1) says that x = 1. In this case (1) is sufficient as it directly answers the question: YES x does equal to 1. This is EXACTLY the case we have with the above question.



Its about the difference between a tautological statement and this question. Reference question : https://gmatclub.com/forum/in-the-diagr ... 94414.html
In the explanation you explained " This statement repeats information in the prompt, and contains no new information, so it doesn’t help us at all to figure out anything else. This statement, alone and by itself, is not sufficient."
Here B is also reintroducing the information in question.
what's the difference ?
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Is st = t ? (1) s = st (2) t = ts 08 Dec 2017, 12:00
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@bunnel If we have a statement that restates the question , then it becomes insufficient as we don't have any additional information to answer the question. But here the equality nullifies it and directly answers the question. Hence it is sufficient. IS this reasoning correct ?
i

Not sure I can follow you.


Say the question asks: is x = 1? And (1) says that x = 1. In this case (1) is sufficient as it directly answers the question: YES x does equal to 1. This is EXACTLY the case we have with the above question.



Its about the difference between a tautological statement and this question. Reference question : https://gmatclub.com/forum/in-the-diagr ... 94414.html
In the explanation you explained " This statement repeats information in the prompt, and contains no new information, so it doesn’t help us at all to figure out anything else. This statement, alone and by itself, is not sufficient."
Here B is also reintroducing the information in question.
what's the difference ?

In the question you quote one of the statements says something that is generally true, so it adds not new info. It says something like x = x, that is generally true.

Here the question asks is \(st = t\)? (2) says t = ts. So, it gives an YES answer to the question.
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Is st = t ? (1) s = st (2) t = ts 16 Apr 2019, 17:44
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thoufique
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Is st = t ?

Is \(st = t\)? --> is \(s=1\) or \(t=0\) (or both)?

(1) s = st --> \(s=0\) or \(t=1\) (or both). Not sufficient.

(2) t = ts. Directly answers the question. Sufficient.

Answer: B.

Hi Bunuel,

from st (1) : we know that 's' not equals 1 or 't' not equals 0 or both , so is this st not sufficient alone.

Pls clarify

Consider this:
If \(s=0\) and \(t\neq{0}\) (\(s = st\)), then \(st\neq{t}\). Or if \(t=1\) and \(s\neq{1}\) (\(s = st\)), then \(st\neq{t}\). So, for these cases the answer to the question is NO.

If \(s=t=0\) (\(s = st\)), then \(st={t}\). Or if \(s=t=1\) (\(s = st\)), then \(st={t}\). So, for these cases the answer to the question is YES.

Does this make sense?

But then for statement 1 isn't the answer 'definitely no' and therefore sufficient?
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Is st = t ? (1) s = st (2) t = ts 07 Feb 2021, 14:30
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What a sneaky question. Fact 2 is literally the originally question but in reverse. It answers itself. SNEAKY!! I'm starting to see the ridiculousness of GMAT questions

Posted from my mobile device
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Is st = t ? (1) s = st (2) t = ts 13 Oct 2021, 01:58
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Under Algebra what is the sub-topic for this? Thanks.
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Is st = t ? (1) s = st (2) t = ts 19 Jan 2024, 03:13
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Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

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