Typewriter Question

[milanproda]

Are there exactly 4 distinct keys that are working on the old typewriter?

1- An old typewriter is defective in such a way that its blank key is not functioning, and the typewriter allows only 4 letters per word by forcing a space character to be inserted after each four letter word. A monkey sitting at the typewriter is aware of this peculiarity, and presses only distinct keys for each four letter sequence. Some keys of this typewriter are not functioning.

2 A monkey is able to create 24 four letter words.

Answer: 3 Both Statements together are sufficient, but neither statement alone is sufficient

????

[Night reader]

Are there exactly 4 distinct keys that are working on the old typewriter?

1- An old typewriter is defective in such a way that its blank key is not functioning, and the typewriter allows only 4 letters per word by forcing a space character to be inserted after each four letter word. A monkey sitting at the typewriter is aware of this peculiarity, and presses only distinct keys for each four letter sequence. Some keys of this typewriter are not functioning.

2 A monkey is able to create 24 four letter words.

Answer: 3 Both Statements together are sufficient, but neither statement alone is sufficient

????

Given: 4 distinct keys, find # keys-? distinct - not ?

st(1) constraint - only 4 letters per word => four slots (places) => monkey is checking the keys -distinct -working -not?
presses only distinct keys, but we don't know how many types monkey presses the keys and how many slots are filled. Not Sufficient;
st(2) monkey arranges all words in 24 ways, but we don't know how many distinct letters (keys) in the words. Not Sufficient;

Combining st(1&2) Find perm for 4 distinct keys placed in 4 slots => 4*3*2*1=24. Sufficient.

Answer C

[milanproda]

Thanks, I did not realize that this was a permutation problem. I assumed that becuase it would to be too time consuming to find all of the possible 4 letter words that the monkey wrote, that stem 2 would be insufficient.