Some chickens and cows are in a farm. These animals have a total of 17 heads and 54 legs.
- How many cows are there?
- How many chickens are there?
Number of cows |
Number of cows' legs |
Number of chickens |
Number of chickens' legs |
Total legs |
17
|
17 x 4 = 68 |
0
|
0
|
68 |
16
|
16 x 4 = 64 |
1
|
1 x 2 = 2 |
66
|
10 |
10 x 4 = 40 |
7
|
7 x 2 = 14 |
54
|
Number of legs if all are cows
= 17 x 4
= 68
Big difference between the number of legs of the cows and the chickens
= 68 - 54
= 14
Small difference between the number of legs of one cow and one chicken
= 4 - 2
= 2
Numbers of chickens
= 14 ÷ 2
= 7
(b)
Number of cows
= 17 - 7
= 10
Answer(s): (a) 7; (b) 10