<PRE><B>Question 1120678</B>
let n be the number of men and x be the number of days
:
after 10 days, there are 4n/5 men
:
x/n is the potion of the provisions per man
:
x/n = (x-10)/(4n/5)
:
cross multiply the fractions
:
4nx/5 = nx -10n
:
multiply both sides of = by 5
:
4nx = 5nx -50n
:
nx = 50n
:
x = 50
:
the provisions last for 50 days
:
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