teal wrote:

There is at least one viper and at least one cobra in Pandora's box. How many cobras are there?

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

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

(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 can not 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.

Can someone please explain me the solution?

Hi,

Consider the following case, V-Viper, C- Cobra,

(C, C, V, V), from this we can have a pair (V, V), (C, V) which satisfy the condition given in statement 1.

but the pair (C, C) has no viper (there should be at least one viper in any pair!), so such pair is not possible.

Thus, there can be only 1 cobra, along with any number of vipers. Sufficient.

Answer (A).

Regards,

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