theres 18 animals in the barnyard, some are cows, some are chickens. there are 50 legs in all, so how many of the animals are cows, and how many are chickens?

Question

this word problem is really stumping me im terrible at word problems 

Answer 1

Kaiah,

 

Let x = number of animals with 4 legs, and (18-x) = number of animals with 2 legs.

 

Then we need to have:  4·x + 2·(18-x) = 50

 

expanding the left side we get:  4·x + 36 - 2·x = 50

 

Simplifying gives:  2·x = 50 - 36 = 14

 

so x = 7 = # of Cows (4 Legs)

 

and 18 - 7 = 11 = # of Chickens (2 Legs)

 

Lets double check:  7 x 4 = 28 and 2 x 11 = 22, and 28 + 22 = 50.  

 

So everything checks out.