There are 2 times as many hamsters as ducks.
There are 90 legs altogether.
- Find the number of animals.
- Find the number of more hamsters than ducks.
- How many less ducks' legs are there than hamsters' legs
| |
Hamsters |
Ducks |
Total |
Difference |
| Number (Animals) |
2 u |
1 u |
3 u |
1 u |
| Value (Legs) |
4 |
2 |
|
|
| Total value (Total legs) |
8 u |
2 u |
10 u |
6 u |
Choose the animal type with a smaller number to be 1 u.
Let the number of ducks be 1 u.
Number of ducks = 1 u
Number of hamsters = 2 u
Number of ducks' legs = 2 x 1 u = 2 u
Number of hamsters' legs = 4 x 2 u = 8 u
Total number of legs
= 8 u + 2 u
= 10 u
10 u = 90
1 u = 90 ÷ 10 = 9
(a)
Number of animals
= 2 u + 1 u
= 3 u
= 3 x 9
= 27
(b)
Number of more hamsters than ducks
= 2 u - 1 u
= 1 u
= 1 x 9
= 9
(c)
Number of less ducks' legs than hamsters' legs
= 8 u - 2 u
= 6 u
= 6 x 9 = 54
Answer(s): (a) 27; (b) 9; (c) 54
