There are 5 times as many sheep as ducks.
There are 440 legs altogether.
- Find the number of animals.
- Find the number of less ducks than sheep.
- Find the number of less ducks' legs than sheep' legs.
|
Sheep |
Ducks |
Total |
Number (Number of animals) |
5 u |
1 u |
6 u |
Value (Number of legs) |
4 |
2 |
|
Total value (Total number of legs) |
5 x 4 = 20 u |
1 x 2 = 2 u |
22 u |
(a)
Let the number of ducks be 1 u.
Number of sheep = 5 u
Number of sheep' legs = 4 x 5 u = 20 u
Number of ducks' legs = 2 x 1 u = 2 u
Total number of legs = 20 u + 2 u = 22 u
22 u = 440
1 u = 440 ÷ 22 = 20
Number of animals
= 5 u + 1 u
= 6 u
= 6 x 20
= 120
(b)
Number of less ducks than sheep
= 5 u - 1 u
= 4 u
= 4 x 20
= 80
(c)
Number of less ducks' legs than sheep' legs
= 20 u - 2 u
= 18 u
= 18 x 20
= 360
Answer(s): (a) 120; (b) 80; (c) 360