Adam has 12 hens and donkeys.
These animals have 36 feet in all.
How many (a) donkeys and (b) hens does Adam have?
| Number of hens |
Number of hens' legs |
Number of donkeys |
Number of donkeys' legs |
Total number of legs between
the hens and the donkeys |
| 12 |
12 x 2 =
24 |
0 |
0 x 4 =
0 |
24 + 0 =
24 |
| 11 |
11 x 2 =
22 |
1 |
1 x 4 =
4 |
22 + 4 =
26 |
| 6 |
6 x 2 =
12 |
12 |
12 x 4 =
48 |
12 + 48 =
36 |
If all of the animals are hens,
the number of legs needed
= 12 x 2
= 24
Total number of extra legs
= 36 - 24
= 12
Difference in the number of legs between 1 donkey and 1 hen
= 4 - 2
= 2
The number of extra legs belongs to the donkeys.
Number of donkeys
= 12 ÷ 2
= 6 (a)
Number of hens
= 12 - 6
= 6 (b)
Answer(s): (a) 6; (b) 6
