Answer is A- 5 days.
Let the work be 2000 completed units:
25 men take 20 days for 2000 units, So 1 man can complete 2000/25 = 80 units in 20 days.
So 1 man can complete 80/20 = 4 units in 1 day______________(1)
15 people leave the job after some days, After they leave the time taken is 37-1/2 days.
Therefore it took 10 people to complet X units in 37.5 days.
10 men can complete 4*10 = 40 units in 1 day_________from (1)
Therefore X = 37.5 * 40 = 1500 units of work.
The remainin 500 units (2000- 1500) was completed by 25 men before 15 men left the job.
Therefore, 25 men took 500 / 4*25 = 5 days to complete 500 units of work.
Therefore , answer is A.
nice q.
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winniethepooh
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alaynaik
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It could also be done as follows:
Let us assume that the 15 men leave after x days,
Therefore, total men days---> 25 * 20 = 25 * x + 10 * 37 1/2 [10 because 15 men leave)
Upon solving the equation we get, x = 5 days
Hence OA = A.
Thanks.
Let us assume that the 15 men leave after x days,
Therefore, total men days---> 25 * 20 = 25 * x + 10 * 37 1/2 [10 because 15 men leave)
Upon solving the equation we get, x = 5 days
Hence OA = A.
Thanks.
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I posted a solution here:Ozlemg wrote:25 men reap a field in 20 days . when should 15 men leave the work.if the whole field is to be reaped in 37-1/2 days after they leave the work?
a.5
b.7
c.15
d.24
e.none
Oa to follow
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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