Newton's Third Law Pair

A few weeks ago I saw a dent in my car as it was parked. I don't know who did it and never will. But I can analyze how exactly it was dented. Since my car was parked, it would be at rest with a velocity of 0 m/s. The car that hit it however, would most likely be reversing (since my front bumper was hit). As the car moved backwards it hit my car applying a force. Let's say this force was 800N. Newton's third law states that for any force exerted onto one object by another, the object exerts a force of equal magnitude and opposite direction. So as this car reversed into mine with a force of 800N, my car should exert the same amount of force. The bumber was still pushed in however. This is similar to question 5 on our review sheet. This is a 3rd law pair. The bumber was dented because it was unable to sustain the amouny of force that was applied. If the bumber was capable of this, it would not have been pushed inward at all. So although both forces were equal, the material of my front bumper can be assumed to be weaker than the other car's back bumper.