* Thickness of the Crust: The thickest part of the Earth's crust is the continental crust, which can be up to 70 kilometers thick.

* Thickness of the Mantle: The mantle extends from the base of the crust to about 2900 kilometers deep.

Calculation:

1. Difference in Thickness: 2900 km (mantle) - 70 km (crust) = 2830 km

2. Ratio: 2830 km (mantle) / 70 km (crust) = 40.43

Answer: The mantle is approximately 40 times thicker than the crust at its thickest point.