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Number of men???

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Number of men???

by mitaliisrani » Thu Aug 26, 2010 5:50 am
A fort of 80 men has food for 45 days. 15 days later reinforcements arrive leaving the number of days the food would last to 20 days. What was the strength of the reinforcement?
A) 60men
B) 50men
C) 40 men
D) 45men
OA is C
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by Gurpinder » Thu Aug 26, 2010 8:49 am
Thats a very awkward question.

Whats the source?
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by akhpad » Thu Aug 26, 2010 9:00 am
Total food available for 45 days
reinforcements arrive after 15 days -> remaining 30 days

Now food lasted in 20 days instead of 30 days

10 days reduced because of reinforcements

Let x be the strength of reinforcements

x * 20 = 80 * 10

x = 40 men
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by beatthegmatinsept » Thu Aug 26, 2010 9:18 am
akhp77 wrote:Total food available for 45 days
reinforcements arrive after 15 days -> remaining 30 days

Now food lasted in 20 days instead of 30 days

10 days reduced because of reinforcements

Let x be the strength of reinforcements

x * 20 = 80 * 10

x = 40 men
Where are you getting the 80 * 10 from? I mean the 10 from?
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by akhpad » Thu Aug 26, 2010 9:26 am
beatthegmatinsept wrote:
akhp77 wrote:Total food available for 45 days
reinforcements arrive after 15 days -> remaining 30 days

Now food lasted in 20 days instead of 30 days

10 days reduced because of reinforcements

Let x be the strength of reinforcements

x * 20 = 80 * 10

x = 40 men
Where are you getting the 80 * 10 from? I mean the 10 from?
No of men initially = 80

Weak Method
80*45 = 80*15 + (80+X) * 20
Last edited by akhpad on Thu Aug 26, 2010 9:35 am, edited 1 time in total.
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by Gurpinder » Thu Aug 26, 2010 9:30 am
and wheres the 80 from buddy?

thanks
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by beatthegmatinsept » Thu Aug 26, 2010 9:36 am
Gurpinder wrote:and wheres the 80 from buddy?

thanks
I think 80 is the initial number of men.
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by akhpad » Thu Aug 26, 2010 9:37 am
Gurpinder wrote:and wheres the 80 from buddy?

thanks
See above my post
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by beatthegmatinsept » Thu Aug 26, 2010 9:40 am
akhp77 wrote:
Gurpinder wrote:and wheres the 80 from buddy?

thanks
See above my post
Makes sense.. Thanks :)
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by thirst4edu » Fri Aug 27, 2010 7:47 am
akhp77 wrote:Total food available for 45 days
reinforcements arrive after 15 days -> remaining 30 days

Now food lasted in 20 days instead of 30 days

10 days reduced because of reinforcements

Let x be the strength of reinforcements

x * 20 = 80 * 10

x = 40 men
Awesome technique, but took long time to understand.. :)
I am sure I cannot come up with such shortcut in less than 2 mins..
Though I solved it with slightly different approach, if it helps somebody..

15 days over, so 45-15=30 days left
80 men 30 days of food

80 men in 30 days, have total food of 2400,
which x+80 men completed in 20 days
20*(x+80) = 2400
x+80=120
x=120-80=40
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