SOLUTION: A goat eats 225 kg. of hay in 45 days, while a cow eats the same amount in 15 days. In how many days could they eat 225 kg. of hay together?

Question 1119804: A goat eats 225 kg. of hay in 45 days, while a cow eats the same amount in 15 days. In how many days could they eat 225 kg. of hay together?
Found 3 solutions by ankor@dixie-net.com, greenestamps, ikleyn:
Answer by ankor@dixie-net.com(22740)   (Show Source): You can put this solution on YOUR website!
A goat eats 225 kg. of hay in 45 days, while a cow eats the same amount in 15 days.
In how many days could they eat 225 kg. of hay together?
:
Find how much each eats in one day
g: 225/45 = 5 kg/day
c: 225/15 = 15 kg/day
:
let d = no. of days for both to eat 225 kg
5d + 15d = 225
20d = 225
d = 225/20
d = 11 days
Answer by greenestamps(13200)   (Show Source): You can put this solution on YOUR website!

The cow eats the same amount as the goat in 1/3 as many days, so the cow is equivalent to 3 goats. Then the goat and the cow together are equivalent to 4 goats.

So, with the goat and the cow, the 225 kg of hay will last 1/4 as long.

45/4 = 11 1/4 days.
Answer by ikleyn(52792)   (Show Source): You can put this solution on YOUR website!
.

1. A goat eats = 5 kg/day. 2. A cow eats = 15 kg/day. 3. Both animals eat together 5 + 15 = 20 kg/day. 4. Both animals will eat 225 kg in = = days.

Solved.

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The lesson to learn from this solution is THIS :

Why use long and complicated approaches when there is SIMPLE and STRAIGHTFORWARD way to get a comprehensive solution ?

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