In a caravan, in addition to 50 hens, there are 45 goats and 8 camels with some keepers. If the total number of feet is 224 more than the number of heads in the caravan, the number of keepers is .....

Hens have two legs, Goats have four, Camels have four legs, and humans have two legs. 

We are told there are 50 hens, which means 100 feet
We are told that there are 45 goats, which means 180 feet
We are told that there are 8 camels, which means 32 feet
Let's say there are X keepers, which means there are 2X feet

The total number of feet will be: 312+2X
The total number of heads will be: 103+X

We are then told that the total number of feet is 224 more than the number of heads.

224+(103+X)=312+2X
327+X=312+2X
X=15

Hence, the number of keepers in the caravan is 15.