Can someone help me with this math question?

Santa Claus was having difficulties. This year he had decided to take as many reindeer as he could find and let a workshop elf ride each one. When he did a count, however, he found he had a problem. There were 4 more elves than there were reindeer, but there were 24 more reindeer legs then elf legs. How many elves and reindeer were there, providing there were no more than 20 of each?