Calculating Force: Car Pushing on Truck with Dead Battery

[ceday]

Homework Statement

A 1000 kg car pushes a 2000 kg truck that has a dead battery. When the driver steps on the accelerator, the drive wheels of the car push against the ground with a force of 4500N . Rolling friction can be neglected.

What is the magnitude of the force of the car on the truck?

Homework Equations

The Attempt at a Solution

I thought it would be 4500N but its not

 

[LowlyPion]

The 4500N force is needed to accelerate both the car and the truck.

What portion of that is needed to accelerate just the truck?