Question

Action and reaction doesn't balance each other why

Answer 1

Action and reaction do balance each other because according to the statement of Newton's third law of motion , to every action an equal and opposite reaction is there.
Only their effect is different on the bodies because of the dissimilarity in their masses. Due to dissimilarity, their inertia is different so same force when acts on a body shows almost no change where as on another body shows huge change.