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# confused

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A group of people, cats, and birds have 70 legs, 30 heads, and 20 tails.  How many cats are in this group?

May 13, 2020

#1
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There are a total of 30 animals, and 10 humans, since 30 -20 = 10.

There are 20 cats and birds, 70 - 10*2 = 50 legs, and 20 tails.

So 4c + 2b = 50

c + b = 50

If there are 10 cats, 10 birds, we have 40 + 20 legs

Too much. 8 cats 12 birds, 32 + 24 = 56 legs.

Each time we remove a cat and add a bird we have 2 less legs. 60-50 = 10, 10/2 = 5/

10-5 = 5cats, 15 birds.

20 + 30 = 50

5 cats

If you don't understand anything feel free to ask.

May 13, 2020

#1
-2

There are a total of 30 animals, and 10 humans, since 30 -20 = 10.

There are 20 cats and birds, 70 - 10*2 = 50 legs, and 20 tails.

So 4c + 2b = 50

c + b = 50

If there are 10 cats, 10 birds, we have 40 + 20 legs

Too much. 8 cats 12 birds, 32 + 24 = 56 legs.

Each time we remove a cat and add a bird we have 2 less legs. 60-50 = 10, 10/2 = 5/

10-5 = 5cats, 15 birds.

20 + 30 = 50

5 cats

If you don't understand anything feel free to ask.

hugomimihu May 13, 2020