Question

A boy pulls a wagon with a force of 6 N east as another boy pushes it with a force of 4 N east. What is the net force?

Answer 1

The answer you are looking for is "2N" because net force is the combination of all the forces acting on an object

Hope this helps!

Answer 2

Both boys are applying forces to the wagon in the same direction,
so the result of both of them is a simple sum of the individual
magnitudes, and still in the same direction.

That's         (6N east + 4N east)  =  10 N east.

That's the net force due to the two boys. 
IF there are no OTHER forces on the wagon,
then it's also the net force on the wagon.                 10 N east