Given:
mantle layer of earth begins about 70 kilometers underneath the surface
outer core begins about 2970 kilometers underneath the surface
Since we need to find the position of each layer relative to the surface, the surface will serve as the point of origin or 0. Below the surface infers a negative value. So, Mantle layer is -70 km from the surface while outer core is -2970 km under the surface.
Comparing -70 and -2970, -70 has a greater value than -2970. The nearer the number is to the origin or 0, the higher its value.
Comparing the absolute greater value of -70 and -2970, -2970 has a greater absolute value. This is because absolute value is the positive value of the number. Absolute value of -70 is 70 while absolute value of -2970 is 2970. Thus, -2970 has a greater absolute value.