There are some horses, chickens and pigs in a farm.There are 2 times as many chickens as pigs. Vanessa finds out that among the animals, there are a total of 31 heads and 88 legs. How many horses are there?
Number of
4-legged animals |
Total legs of
4-legged animals |
Number of
2-legged animals |
Total legs of
2-legged animals |
Total legs |
31
|
31 x 4 =
124 |
0
|
0
|
124
|
30
|
30 x 4 =
120 |
1
|
1 x 2 =
2 |
122
|
13
|
13 x 4 =
52 |
18
|
18 x 2 =
36 |
36 |
Total number of legs if all are 4-legged animals
= 4 x 31
= 124
Big difference between all the 2-legged animals and all the 4-legged animals
= 124 - 88
= 36
Small difference between one 2-legged animal and one 4-legged animal
= 4 - 2
= 2
Number of chickens
= 36 ÷ 2
= 18
Number of 4-legged animals
= 31 - 18
= 13
Number of pigs = 1 u
Number of chickens = 2 u
2 u = 18
1 u = 18 ÷ 2 = 9
Number of pigs
= 1 u
= 9
Number of horses
= 13 - 9
= 4
Answer(s): 4
