Some children were riding on the bus. At the bus stop 14 more children got on the bus. Then there were 4 children altogether on the bus. How many children were riding on the bus before the bus stop?
There were some children riding on the bus. 
At the bus stop, 14 more children got on the bus. 
That means there were a total of 14 + some children on the bus. 
We know that there were 4 children altogether on the bus, so we can set up the equation: 

14 + some = 4 

We can solve this equation to find out how many children were riding on the bus before the bus stop. 

some = 4 - 14 
some = -10 

That means there were 10 children riding on the bus before the bus stop.