Roger can chop down 4 trees in an hour. How long does it take Vincent

Question

Roger can chop down 4 trees in an hour. How long does it take Vincent to chop down 4 trees?

(1) Vincent spends 6 hours per day chopping down trees.
(2) Vincent takes twice as long as Roger to chop down trees.

Nikkb · Answer

Roger can chop down 4 trees in an hour.
Find : How long does it take Vincent to chop down 4 trees?

(1) Vincent spends 6 hours per day chopping down trees.
=> statement does not tell how many tress Vincent cut in a day. SO we cannot no. of hours he take to cut 4 trees 
Insufficient

(2) Vincent takes twice as long as Roger to chop down trees.
=> V = 2* R 
=> If R takes 1 hour to cut 4 tree, Vincent will take 2 hour to cut 4 trees.
Sufficient

Answer: B

surbhipuri · Answer

Statement 2 only mentions trees how can we assume 4 trees .I was confuse between c and e .

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Nikkb · Answer

Statement 2 says: Vincent takes twice as long as Roger to chop down trees.

so example if Roger takes 15 min to chop 1 tree Vincent will take 2*15 = 30 mins to chop 1 tree
Or if Roger takes 5 hours to chop x trees Vincent will take 2*5 = 10 hours to chop same number of trees ie x trees

So just whatever time Roger take to complete a work Vincent will take double of time to do same amount of work.

In question stem Given that -> Roger takes 1 hour to chop 4 trees => Vincent will take 2*1 = 2 hour to do same work ie to chop 4 trees.

And that is the question. We have to find number of hours taken by vincent to chop 4 trees.
So statement 2 is sufficient.
Answer: B

Roger can chop down 4 trees in an hour. How long does it take Vincent

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