SOLUTION: Please Help me solve this question A garrison has provisions for a certain number of days; after 10 days 1/5 of the men desert and it is found the provisions will last just as

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: Please Help me solve this question A garrison has provisions for a certain number of days; after 10 days 1/5 of the men desert and it is found the provisions will last just as       Log On


   



Question 1120678: Please Help me solve this question
A garrison has provisions for a certain number of days; after 10 days 1/5 of the men desert and it is found the provisions will last just as long as before; how long was that?

Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
let n be the number of men and x be the number of days
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after 10 days, there are 4n/5 men
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x/n is the potion of the provisions per man
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x/n = (x-10)/(4n/5)
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cross multiply the fractions
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4nx/5 = nx -10n
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multiply both sides of = by 5
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4nx = 5nx -50n
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nx = 50n
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x = 50
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the provisions last for 50 days
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