There are 2 times as many guinea pigs as parrots.
There are 20 legs altogether.
- Find the number of animals.
- Find the number of more guinea pigs than parrots.
- How many less parrots' legs are there than guinea pigs' legs
| |
Guinea Pigs |
Parrots |
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 parrots be 1 u.
Number of parrots = 1 u
Number of guinea pigs = 2 u
Number of parrots' legs = 2 x 1 u = 2 u
Number of guinea pigs' legs = 4 x 2 u = 8 u
Total number of legs
= 8 u + 2 u
= 10 u
10 u = 20
1 u = 20 ÷ 10 = 2
(a)
Number of animals
= 2 u + 1 u
= 3 u
= 3 x 2
= 6
(b)
Number of more guinea pigs than parrots
= 2 u - 1 u
= 1 u
= 1 x 2
= 2
(c)
Number of less parrots' legs than guinea pigs' legs
= 8 u - 2 u
= 6 u
= 6 x 2 = 12
Answer(s): (a) 6; (b) 2; (c) 12
