At a farm, there were
79 as many ducks and pigs. The farmer added another 29 ducks but sold away 42 pigs. In the end, there were 7 pigs more than ducks. How many ducks and pigs were there altogether in the end?
| |
Ducks |
Pigs |
| Before |
7 u |
9 u |
| Change |
+ 29 |
- 42 |
| After |
7 u + 29 |
9 u - 42 |
If the farmer had another 7 ducks in the end, the number of ducks and (chickens) would be the same.
9 u - 42 = 7 u + 29 + 7
9 u - 7 u = 36 + 42
2 u = 78
1 u = 78 ÷ 2 = 39
Number of pigs and ducks in the end
= 7 u + 29 + 9 u - 42
= 7 u + 9 u + 29 - 42
= 16 u - 13
= 16 x 39 - 13
= 611
Answer(s): 611
