Some ducks and pigs are in a farm. These animals have a total of 16 heads and 54 legs.
- How many pigs are there?
- How many ducks are there?
Number of
pigs |
Number of
pigs' legs |
Number of
ducks |
Number of
ducks' legs |
Total legs |
16
|
16 x 4
= 64 |
0
|
0
|
64 |
15
|
15 x 4
= 60 |
1
|
1 x 2
= 2 |
62
|
| 11 |
11 x 4
= 44 |
5
|
5 x 2
= 10 |
54
|
Number of legs if all are pigs
= 16 x 4
= 64
Big difference between the number of legs of the pigs and the ducks
= 64 - 54
= 10
Small difference between the number of legs of one pig and one duck
= 4 - 2
= 2
Numbers of ducks
= 10 ÷ 2
= 5
(b)
Number of pigs
= 16 - 5
= 11
Answer(s): (a) 5; (b) 11
