There are a total of 776 sheep, donkeys, ducks and chickens at a farm. The number of ducks was 400 more than the number of sheep. The total number of donkeys and chickens was 2 times the number of sheep.
- How many donkeys and chickens were there at the farm?
- The total number of legs for all the donkeys and chickens was 684. How many donkeys were there in the farm?
(a)
Number of sheep = 1 u
Number of donkeys and chickens = 2 u
Number of ducks = 1 u + 400
Total number of animals
= 1 u + 2 u + 1 u + 400
= 4 u + 400
4 u + 400 = 776
4 u = 776 - 400
4 u = 376
1 u = 376 ÷ 4 = 94
Number of donkeys and chickens
= 2 u
= 2 x 94
= 188
(b)
Number of
donkeys |
Number of
donkeys' legs |
Number of
chickens |
Number of
chickens' legs |
Total
|
188
|
188 x 4 =
752 |
0
|
0
|
752
|
187
|
187 x 4 =
748 |
1
|
1 x 2 =
2 |
750
|
154
|
154 x 4 =
616 |
34
|
34 x 2=
68 |
684
|
Total number of donkeys and chickens = 188
Total number of legs if all of them are donkeys
= 188 x 4
= 752
Big difference in the total number of legs between the donkeys and the chickens
= 752 - 684
= 68
Small difference in number of legs between one donkey and one chicken
= 4 - 2
= 2
Number of chickens
= 68 ÷ 2
= 34
Number of donkeys
= 188 - 34
= 154
Answer(s): (a) 188; (b) 154
