I think that in most formal English style not dealing with technical subjects, the usual way would be  five cats and 50 elephants,  
while universally in a true list or table it would be 
 cats:  5
 elephants: 50
But certainly within the context of finance or engineering or the like, the numerical style is always used. 
In the Sandy Koufax article, line 93 plus, we have 5th day  4th day  which is OK, as is  fifth day  fourth day and 
in the same sentence 34 starts 41 starts 7 fewer starts. which is OK, but the one thing that would strike a reader as  wrong would be 34 starts, 41 starts, seven starts. Speaking for myself, why change a consistent article when there are so many that are not consistent in need of improvement?