maths question
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maths question
Hi can someone help with this maths question.
2 dogs take 18 days to eat some dog food. how long will it take 3 dogs to eat the same amount of food.
thank you
2 dogs take 18 days to eat some dog food. how long will it take 3 dogs to eat the same amount of food.
thank you
Re: maths question
How long would the food last for one dog?2 dogs take 18 days to eat some dog food. how long will it take 3 dogs to eat the same amount of food.
It would last 2 x 18 ie 36 days
So if there were 3 dogs ..36 divided by 3 = 12
Re: maths question
or put another way ⅔ of 18
the number of dogs is 1½ times what it was before -
so 18 / 1½ (or 3/2)
invert the fraction and change divide to multiply to get
18 x ⅔
the number of dogs is 1½ times what it was before -
so 18 / 1½ (or 3/2)
invert the fraction and change divide to multiply to get
18 x ⅔
Re: maths question
That's not a very clear method imho - inverse proportion needs explanation.
Re: maths question
If it takes 2 dogs 18 days, then on his own, it would take one dog 36 days.
Therefore, 3 dogs would divide the food equally 36 / 3 = 12.
It would take 12 days, as the other two have said.
Therefore, 3 dogs would divide the food equally 36 / 3 = 12.
It would take 12 days, as the other two have said.
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