Question

7) On a farm, there are some cows and birds.

There are 35 total heads and 110 total
legs. How many cows and how many
birds are there?

Answer 1

Explanation:

"On a farm, there are some cows and birds."

c and b are the number of cows and birds, respectively.

"There are 35 total heads"

c+b = 35

b = 35-c

"110 total legs."

4c + 2b = 110

4c + 2(35-c) = 110

4c + 70 - 2c = 110

2c = 40

c = 20

b = 35-c = 15

20 cows and 15 birds.