If 9 cows can eat 4 bales of hay in 5 days, how long will it take 4 cows to eat 17 bales of hay?
I do not remember how to do this at all
If 9 cows can eat 4 bales of hay in 5 days, how long will it take 4 cows to eat 17 bales of hay?
I do not remember how to do this at all
“... mathematics is only the art of saying the same thing in different words” - B. Russell
This is where the unit analysis will help [and I'm doing it 'upside down from what Subhotosh Khan did, but the answer should be the same]. So the Rate R of using hay is
R = 4 bales per (9*5 cow-day) = 4 bales / (9*5 cow-day)
or
R = (4/45) bales /cow-day
Thus, at the same rate we want
R = (4/45) bales /cow-day = 17 bales / (4 * x cow-day)
or
x = 17 / 4 / (4/45) = 17 * 45 / 16
Is that how you approach all math problems? "Remembering" how to do them? What ever became of thinking?
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