<PRE><B>Question 1143938</B>
5 sheep ate 150 kg of grass in 15 days.
general formula is n * r * t = q
n is the number of sheep
r is the rate that each sheep eats grass
t is the time
q is quantity of grass eaten
when n = 5 and q = 150 kilograms and t = 15 days, the formula becomes:
5 * r * 15 = 150
solve for r to get r = 150 / 75 = 2.
the rate that each sheep eats grass is 2 kilograms per day.
when n = 9 and r = 2 and q = 90 kilograms, the formula becomes:
9 * 2 * t = 90
solve for t to get t = 90 / 18 = 5
9 sheep will eat 90 kilograms in 5 days.


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