There are some cows, ducks and buffaloes in a farm.There are 2 times as many ducks as buffaloes. Betty finds out that among the animals, there are a total of 22 heads and 72 legs. How many cows 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 |
22
|
22 x 4 =
88 |
0
|
0
|
88
|
21
|
21 x 4 =
84 |
1
|
1 x 2 =
2 |
86
|
14
|
14 x 4 =
56 |
8
|
8 x 2 =
16 |
16 |
Total number of legs if all are 4-legged animals
= 4 x 22
= 88
Big difference between all the 2-legged animals and all the 4-legged animals
= 88 - 72
= 16
Small difference between one 2-legged animal and one 4-legged animal
= 4 - 2
= 2
Number of ducks
= 16 ÷ 2
= 8
Number of 4-legged animals
= 22 - 8
= 14
Number of buffaloes = 1 u
Number of ducks = 2 u
2 u = 8
1 u = 8 ÷ 2 = 4
Number of buffaloes
= 1 u
= 4
Number of cows
= 14 - 4
= 10
Answer(s): 10
