During summer break 2 kids from Lawrence county go to camp and the other 40 kids stay home. An additional 19 kids from outside the county attended the camp. About how many kids are in Lawrence county?
There are 2 kids from Lawrence county who go to camp. 
There are 40 kids from Lawrence county who stay home. 
That means there are 42 kids from Lawrence county in total. 

We're told that there are 19 kids from outside the county who attended the camp. 

That means that the total number of kids who attended the camp is 42 + 19, or 61.