There are external and internal representations for a quantum state W. External representation is commonly adopted in the standard quantum mechanics by exploiting probability density function W*W to explain the observed interference fringes in slit experiments. On the other hand, in quantum Hamilton mechanics, the quantum state W has a dynamical representation that reveals the internal mechanism underlying the externally observed interference fringes. The internal representation of W is described by a set of Hamilton equations of motion, by which quantum trajectories of a particle moving in W can be solved. In this article, millions of complex quantum trajectory connecting slits to a screen are solved from the Hamilton equations, and the statistical distribution of their arrivals on the screen is shown to reproduce the observed interference fringes. This appears to be the first quantitative verification of the equivalence between the trajectory-based statistics and the wavefunction-based statistics on slit experiments.