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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Number of men???
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mitaliisrani
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akhpad
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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
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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beatthegmatinsept
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Where are you getting the 80 * 10 from? I mean the 10 from?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
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akhpad
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No of men initially = 80beatthegmatinsept wrote:Where are you getting the 80 * 10 from? I mean the 10 from?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
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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beatthegmatinsept
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I think 80 is the initial number of men.Gurpinder wrote:and wheres the 80 from buddy?
thanks
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beatthegmatinsept
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Makes sense.. Thanksakhp77 wrote:See above my postGurpinder wrote:and wheres the 80 from buddy?
thanks
Being defeated is often only a temporary condition. Giving up is what makes it permanent.
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thirst4edu
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Awesome technique, but took long time to understand..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
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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