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What is the ratio of the amount, by weight, of Metal A to Metal B in A 30 May 2024, 11:02
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­What is the ratio of the amount, by weight, of Metal A to Metal B in Alloy K?

(1) The ratio of Metal A to Metal B in Alloy K becomes 5:6 when 40 pounds of Metal A is added to the alloy.

(2) The ratio of Metal A to Metal B in Alloy K becomes 7:6 when 60 pounds of Metal A is added to the alloy.­
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C
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What is the ratio of the amount, by weight, of Metal A to Metal B in A 03 Jun 2024, 06:37
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 Post subject: What is the ratio of the amount, by weight, of Metal A to Metal B in A  Posted: 30 May 2024, 10:02
­What is the ratio of the amount, by weight, of Metal A to Metal B in Alloy K?

(1) The ratio of Metal A to Metal B in Alloy K becomes 5:6 when 40 pounds of Metal A is added to the alloy.

(2) The ratio of Metal A to Metal B in Alloy K becomes 7:6 when 60 pounds of Metal A is added to the alloy.­
­Ratio = A:B
statement 1: 40 pounds of A added.
A becomes = A+40 , B remains same
A+40/B = 5/6
6A + 240 = 5B
Not sufficient

Statement 2: 60 pounds of A added.
A becomes = A+60 , B remains same
A+60/B = 7/6
6A + 360 = 7B
Not sufficient

Statement 1 & 2
6A+240=5B
6A+360=7B
SUFFICIENT
 
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What is the ratio of the amount, by weight, of Metal A to Metal B in A 07 Mar 2025, 09:46
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Post subject: What is the ratio of the amount, by weight, of Metal A to Metal B in A Posted: 30 May 2024, 10:02
­What is the ratio of the amount, by weight, of Metal A to Metal B in Alloy K?

(1) The ratio of Metal A to Metal B in Alloy K becomes 5:6 when 40 pounds of Metal A is added to the alloy.

(2) The ratio of Metal A to Metal B in Alloy K becomes 7:6 when 60 pounds of Metal A is added to the alloy.­
­Ratio = A:B
statement 1: 40 pounds of A added.
A becomes = A+40 , B remains same
A+40/B = 5/6
6A + 240 = 5B
Not sufficient

Statement 2: 60 pounds of A added.
A becomes = A+60 , B remains same
A+60/B = 7/6
6A + 360 = 7B
Not sufficient

Statement 1 & 2
6A+240=5B
6A+360=7B
SUFFICIENT
Show more
Can you plz explain how together they are sufficient?
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What is the ratio of the amount, by weight, of Metal A to Metal B in A 08 Mar 2025, 00:14
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RIqO
Post subject: What is the ratio of the amount, by weight, of Metal A to Metal B in A Posted: 30 May 2024, 10:02
­What is the ratio of the amount, by weight, of Metal A to Metal B in Alloy K?

(1) The ratio of Metal A to Metal B in Alloy K becomes 5:6 when 40 pounds of Metal A is added to the alloy.

(2) The ratio of Metal A to Metal B in Alloy K becomes 7:6 when 60 pounds of Metal A is added to the alloy.­
­Ratio = A:B
statement 1: 40 pounds of A added.
A becomes = A+40 , B remains same
A+40/B = 5/6
6A + 240 = 5B
Not sufficient

Statement 2: 60 pounds of A added.
A becomes = A+60 , B remains same
A+60/B = 7/6
6A + 360 = 7B
Not sufficient

Statement 1 & 2
6A+240=5B
6A+360=7B
SUFFICIENT
Can you plz explain how together they are sufficient?

Statement 1 & 2
6A+240=5B
6A+360=7B
Show more

If you look at statements 1 and 2, you can subtract it. Simply speaking, just imagine the 6A cuts out. You will get the value of B, i.e., 60. Put the value of B in any of the two equations and you will get A. Hence obtaining the ration of metals A to B.
Therefore, it is sufficient.
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What is the ratio of the amount, by weight, of Metal A to Metal B in A 02 Jul 2025, 08:00
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GMATNinja I do feel this question is wrong at some level, if i were to think of the possible solutions using only statement 2. I would end up on ratio of 1:6 which indeed is the answer of the question on combining the statement. Let me know if i am wrong, I got this ques wrong while attempting on the official portal but I have checked for all the cases. It will start repeating for when B is 12 but then A would be 2, that does mean that ratio is 1:6.
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What is the ratio of the amount, by weight, of Metal A to Metal B in A 02 Jul 2025, 08:03
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I have been practicing DS as i found that it was a weakness for me, and I have started taking the approach to disapprove the statement to make sure I am correct. For the first statement i found multiple diff ratios hence I rejected it for this one I couldn't do the same. Unless my premise is wrong that A needs to be an integer I guess in which case there could be a lot of answer choices.

Pr4n
GMATNinja I do feel this question is wrong at some level, if i were to think of the possible solutions using only statement 2. I would end up on ratio of 1:6 which indeed is the answer of the question on combining the statement. Let me know if i am wrong, I got this ques wrong while attempting on the official portal but I have checked for all the cases. It will start repeating for when B is 12 but then A would be 2, that does mean that ratio is 1:6.
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What is the ratio of the amount, by weight, of Metal A to Metal B in A 02 Jul 2025, 23:19
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­What is the ratio of the amount, by weight, of Metal A to Metal B in Alloy K?

(1) The ratio of Metal A to Metal B in Alloy K becomes 5:6 when 40 pounds of Metal A is added to the alloy.

(2) The ratio of Metal A to Metal B in Alloy K becomes 7:6 when 60 pounds of Metal A is added to the alloy.­

I have been practicing DS as i found that it was a weakness for me, and I have started taking the approach to disapprove the statement to make sure I am correct. For the first statement i found multiple diff ratios hence I rejected it for this one I couldn't do the same. Unless my premise is wrong that A needs to be an integer I guess in which case there could be a lot of answer choices.

Pr4n
GMATNinja I do feel this question is wrong at some level, if i were to think of the possible solutions using only statement 2. I would end up on ratio of 1:6 which indeed is the answer of the question on combining the statement. Let me know if i am wrong, I got this ques wrong while attempting on the official portal but I have checked for all the cases. It will start repeating for when B is 12 but then A would be 2, that does mean that ratio is 1:6.
Show more

First of all, we are not told that the weights must be integers. Even if we were, the equation from (2), 6A + 360 = 7B, allows for multiple (A, B) pairs that satisfy it, such as (17, 66), (24, 72), (31, 78), and so on.

However, the main issue is the incorrect assumption that A and B must be integers. If you drop that assumption, it is clear that 6A + 360 = 7B has infinitely many solutions, so there is no need to check any specific values. Similarly, from (1), 6A + 240 = 5B, also has infinitely many solutions without needing to test values.

When taken together, we have two distinct linear equations: 6A + 240 = 5B and 6A + 360 = 7B. With two equations and two variables, we can solve for A and B uniquely, and there is no need to check values or even actually solve.

So, as you can see, with the correct approach, when not assuming anything that is not explicitly given, you can solve this question without any algebra or number plugging, in less than a minute.
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What is the ratio of the amount, by weight, of Metal A to Metal B in A 03 Jul 2025, 05:16
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Thanks! I did realise later as it wasn't given in the question and also it was a ratio question, hence I don't need to assume that it should be an integer unlike coins or books (things that are meant to be integers). But additionally, i guess i never went to the values you have mentioned so that also helps. I guess it was just my overcompensation for my weakness and overthinking which made me ignore the fact that A & B are not integers in the first place.

Bunuel
Pr4n
­What is the ratio of the amount, by weight, of Metal A to Metal B in Alloy K?

(1) The ratio of Metal A to Metal B in Alloy K becomes 5:6 when 40 pounds of Metal A is added to the alloy.

(2) The ratio of Metal A to Metal B in Alloy K becomes 7:6 when 60 pounds of Metal A is added to the alloy.­

I have been practicing DS as i found that it was a weakness for me, and I have started taking the approach to disapprove the statement to make sure I am correct. For the first statement i found multiple diff ratios hence I rejected it for this one I couldn't do the same. Unless my premise is wrong that A needs to be an integer I guess in which case there could be a lot of answer choices.

Pr4n
GMATNinja I do feel this question is wrong at some level, if i were to think of the possible solutions using only statement 2. I would end up on ratio of 1:6 which indeed is the answer of the question on combining the statement. Let me know if i am wrong, I got this ques wrong while attempting on the official portal but I have checked for all the cases. It will start repeating for when B is 12 but then A would be 2, that does mean that ratio is 1:6.

First of all, we are not told that the weights must be integers. Even if we were, the equation from (2), 6A + 360 = 7B, allows for multiple (A, B) pairs that satisfy it, such as (17, 66), (24, 72), (31, 78), and so on.

However, the main issue is the incorrect assumption that A and B must be integers. If you drop that assumption, it is clear that 6A + 360 = 7B has infinitely many solutions, so there is no need to check any specific values. Similarly, from (1), 6A + 240 = 5B, also has infinitely many solutions without needing to test values.

When taken together, we have two distinct linear equations: 6A + 240 = 5B and 6A + 360 = 7B. With two equations and two variables, we can solve for A and B uniquely, and there is no need to check values or even actually solve.

So, as you can see, with the correct approach, when not assuming anything that is not explicitly given, you can solve this question without any algebra or number plugging, in less than a minute.
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What is the ratio of the amount, by weight, of Metal A to Metal B in A 16 Jul 2025, 08:11
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I think this questions deserves appreciation. Made the mistake of considering A and B are the only metals in the alloy.
If it would had been the case, answer would have been D.

Further this can easily be turned into the tough PS question. I suggest solving the same question in order to calculate the difference metal percentage in alloy, considering A and B as only metals in the alloy and either of statement 1 or 2 as given condition.

bb - Do you think this may included in focus mocks
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What is the ratio of the amount, by weight, of Metal A to Metal B in A 15 Aug 2025, 04:09
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­What is the ratio of the amount, by weight, of Metal A to Metal B in Alloy K?

(1) The ratio of Metal A to Metal B in Alloy K becomes 5:6 when 40 pounds of Metal A is added to the alloy.

(2) The ratio of Metal A to Metal B in Alloy K becomes 7:6 when 60 pounds of Metal A is added to the alloy.­
Show more
I think the answer should be E, As we are not told the amount of alloy is same in statement (1) and (2).

Suppose in X lbs of alloy, let there be A lbs of metal A and B lbs of metal B.
Now, statement 1 says: (A+40)/B = 5/6. {considering 40 lbs of metal A was added to X lbs of alloy}

However, statement 2 could mean: (2A+60)/2B = 7/6 {considering 60 lbs of metal A was added to 2X lbs of alloy}.
The equation could keep changing once you keep changing the total amount of alloy.


Hence, we cannot say answer is C, unless we know that both the statements are talking about the same absolute amount of alloy K.
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What is the ratio of the amount, by weight, of Metal A to Metal B in A 15 Aug 2025, 06:49
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guddo
­What is the ratio of the amount, by weight, of Metal A to Metal B in Alloy K?

(1) The ratio of Metal A to Metal B in Alloy K becomes 5:6 when 40 pounds of Metal A is added to the alloy.

(2) The ratio of Metal A to Metal B in Alloy K becomes 7:6 when 60 pounds of Metal A is added to the alloy.­
I think the answer should be E, As we are not told the amount of alloy is same in statement (1) and (2).

Suppose in X lbs of alloy, let there be A lbs of metal A and B lbs of metal B.
Now, statement 1 says: (A+40)/B = 5/6. {considering 40 lbs of metal A was added to X lbs of alloy}

However, statement 2 could mean: (2A+60)/2B = 7/6 {considering 60 lbs of metal A was added to 2X lbs of alloy}.
The equation could keep changing once you keep changing the total amount of alloy.


Hence, we cannot say answer is C, unless we know that both the statements are talking about the same absolute amount of alloy K.
Show more

Both statements talk about the same Alloy K, so your reasoning is incorrect. This is an official question, and the correct answer is C, not E.

What is the ratio of the amount, by weight, of Metal A to Metal B in Alloy K?

(1) The ratio of Metal A to Metal B in Alloy K becomes 5:6 when 40 pounds of Metal A is added to the alloy.

(2) The ratio of Metal A to Metal B in Alloy K becomes 7:6 when 60 pounds of Metal A is added to the alloy
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What is the ratio of the amount, by weight, of Metal A to Metal B in A 15 Aug 2025, 23:32
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guddo
­What is the ratio of the amount, by weight, of Metal A to Metal B in Alloy K?

(1) The ratio of Metal A to Metal B in Alloy K becomes 5:6 when 40 pounds of Metal A is added to the alloy.

(2) The ratio of Metal A to Metal B in Alloy K becomes 7:6 when 60 pounds of Metal A is added to the alloy.­
I think the answer should be E, As we are not told the amount of alloy is same in statement (1) and (2).

Suppose in X lbs of alloy, let there be A lbs of metal A and B lbs of metal B.
Now, statement 1 says: (A+40)/B = 5/6. {considering 40 lbs of metal A was added to X lbs of alloy}

However, statement 2 could mean: (2A+60)/2B = 7/6 {considering 60 lbs of metal A was added to 2X lbs of alloy}.
The equation could keep changing once you keep changing the total amount of alloy.


Hence, we cannot say answer is C, unless we know that both the statements are talking about the same absolute amount of alloy K.

Both statements talk about the same Alloy K, so your reasoning is incorrect. This is an official question, and the correct answer is C, not E.

What is the ratio of the amount, by weight, of Metal A to Metal B in Alloy K?

(1) The ratio of Metal A to Metal B in Alloy K becomes 5:6 when 40 pounds of Metal A is added to the alloy.

(2) The ratio of Metal A to Metal B in Alloy K becomes 7:6 when 60 pounds of Metal A is added to the alloy
Show more
Both statements are talking about Alloy K, but not specifically talking about the same quantity of Alloy K. What if 40 lbs of metal A is added in 100 lbs of Alloy K, but 60 lbs of metal A is added in 200 lbs of Alloy K?
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What is the ratio of the amount, by weight, of Metal A to Metal B in A 16 Aug 2025, 01:35
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Both statements are talking about Alloy K, but not specifically talking about the same quantity of Alloy K. What if 40 lbs of metal A is added in 100 lbs of Alloy K, but 60 lbs of metal A is added in 200 lbs of Alloy K?
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You are overcomplicating it. Both statements clearly talk about the same Alloy K with the same fixed starting amounts of metals A and B. Alloy K is not changing between the statements, so your interpretation with different quantities does not apply.
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