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This is a hard question that challenges test-taker's logic. It is simple once you understand it but hard if you have never solved it. If you made a mistake on this question, make sure you understand the logic so you can be armed with this new tool for the real test.

(1) Statement 1 tells us that from any two snakes from Pandora's box at least one is a viper. This does not mean that there are 2 snakes in the box or that there is only 1 viper. Instead, it indicates that at most, there is 1 cobra. This may mean 1 cobra and 1 viper or 1 cobra and 99 vipers. Make sure you understand this distinction. S1 tells us that there is only 1 cobra in the box, which is sufficient.

(2) The total number of snakes Pandora's box is 99. Clearly insufficient.

(1) From any two snakes from Pandora's box at least one is a viper. Since from ANY two snakes one is a viper then there cannot be 2 (or more) cobras and since there is at least one cobra then there must be exactly one cobra in the box. Sufficient.

(2) The total number of snakes Pandora's box is 99. Clearly insufficient.

Answer: A

Hi Bunuel, Any specific types/patterns of word problems that you could suggest here.

Facing a lot of time issues especially when these word problems come in DS mode.

(1) From any two snakes from Pandora's box at least one is a viper. Since from ANY two snakes one is a viper then there cannot be 2 (or more) cobras and since there is at least one cobra then there must be exactly one cobra in the box. Sufficient.

(2) The total number of snakes Pandora's box is 99. Clearly insufficient.

Answer: A

Hi Please do reply

From any two snakes from Pandora's box at least one is a viper does not it mean that if 2 snakes were taken out from the box at least one is viper if you consider this will the answer be different

(1) From any two snakes from Pandora's box at least one is a viper. Since from ANY two snakes one is a viper then there cannot be 2 (or more) cobras and since there is at least one cobra then there must be exactly one cobra in the box. Sufficient.

(2) The total number of snakes Pandora's box is 99. Clearly insufficient.

Answer: A

Hi Please do reply

From any two snakes from Pandora's box at least one is a viper does not it mean that if 2 snakes were taken out from the box at least one is viper if you consider this will the answer be different

Yes, it means exactly that. But what do you mean that the answer would be different?
_________________

(1) From any two snakes from Pandora's box at least one is a viper. Since from ANY two snakes one is a viper then there cannot be 2 (or more) cobras and since there is at least one cobra then there must be exactly one cobra in the box. Sufficient.

(2) The total number of snakes Pandora's box is 99. Clearly insufficient.

Answer: A

Hi Please do reply

From any two snakes from Pandora's box at least one is a viper does not it mean that if 2 snakes were taken out from the box at least one is viper if you consider this will the answer be different

Yes, it means exactly that. But what do you mean that the answer would be different?

Sorry got it now irrespective of the no of vipers, cobra can never be more than 1.

It took me sometime to understand statement 1 in the test. For those having trouble like me, hope this helps! Statement 1: Any 2 snakes, possibilities ---> V, V or V, C or C, V. There is no possibility for C, C. This means that there is only 1 cobra in the box. Sufficient.

Statement 2: Totally irrelevant and useless.
_________________

Cheers!!

JA If you like my post, let me know. Give me a kudos!

Yes but we do know know how many snakes there are in the box.

For example if the number of snakes is 10 there could be 9 ; 1 or it could be 5;5.

Second one is clearly insufficient also

And both are insufficient.

99 Snakes 1 cobra 98 vipers, or 97/2

Please explain

Thank you

Let me ask you if there are 5 vipers and 5 cobras, would the second statement be correct?

Hey Bunuel, it's still not clear for me concerning answer (1).

If we take your example with 10 snakes, doesn't it mean that we can have anything from (5V 5C; 6V 4C;...9V 1C) according to statement 1? A ratio of 6:4 V to C is still "at least 1 viper" for any 2 snakes.

Thanks for clarifying.
_________________

THANKS = KUDOS. Kudos if my post helped you!

Napoleon Hill — 'Whatever the mind can conceive and believe, it can achieve.'

Yes but we do know know how many snakes there are in the box.

For example if the number of snakes is 10 there could be 9 ; 1 or it could be 5;5.

Second one is clearly insufficient also

And both are insufficient.

99 Snakes 1 cobra 98 vipers, or 97/2

Please explain

Thank you

Let me ask you if there are 5 vipers and 5 cobras, would the second statement be correct?

Hey Bunuel, it's still not clear for me concerning answer (1).

If we take your example with 10 snakes, doesn't it mean that we can have anything from (5V 5C; 6V 4C;...9V 1C) according to statement 1? A ratio of 6:4 V to C is still "at least 1 viper" for any 2 snakes.

Thanks for clarifying.

NO. We cannot have more than 1 cobras. If there are 5 cobras and 5 vipers then the first statement will NOT hold. (1) says from ANY two snakes from Pandora's box at least one is a viper. If there are 5 cobras and 5 vipers then we could have two snakes from which BOTH are vipers.
_________________

Excellent question, but I'm partial because I got it right. It's more representative of the type of thinking on the verbal portion of the exam, IMO, which is another reason I like it, and it also reminded me of the Monty Hall problem for whatever reason.

To people who are still confused about the 1st statement the below example should help you.

Ex:

Stated in the question There is at least one viper and at least one cobra in Pandora's box

Statement 1 From any two snakes from Pandora's box at least one is a viper.

Cases that are in scope and are correct are 1V 1C is correct 2V 1C is correct 3V 1C is correct . . . n-1V 1C is correct where n >0 and n is an integer

Here the no of cobras are always one because in the question it is stated that there is at least one cobra in Pandora's box. So minimum value of no of cobras is 1

Note: Cases that are out of scope. 1V 2C 2V 2C 3V 3C etc...

Notice the no of cobras is always greater one . But what does the statement 1 say "from any two snakes at least one is a viper." So all the above cases are out of scope as there is a chance that from any two snakes none can be a viper.

Look at the question. The condition u mentioned is out of scope. The question clearly says that there is atleast one V and one C in the box. You should not consider the case where cobras are 0.

When only the condition in the question is considered

Possible cases are 1v 1c 2v 2c Etc

Cases that are out of scope 1v 0c 2v 0c 3v 0c . . . Nv 0c 0v 1c 0v 2c 0v 3c . . . 0v Nc

Please elaborate on this. The question is perfectly valid, though quite hard.

Interesting solution, but not sure how this is math (not counting/probability/algebra/arithmetic etc.) More like it was a question testing your logical deduction.