Answer:
We can use the tan trig ratio to calculate the steepness of each run.
The side opposite the angle is the vertical distance of each path.
The side adjacent to the angle is the horizontal distance of each path.
(see attached diagram)
Tan trig ratios

where:
is the angle- O is the side opposite the angle
- A is the side adjacent the angle
Little Thunder



Rating = EASY (green circle)
Dodge Ridge



Rating = MODERATE (blue square)
Wild Side



Rating = DIFFICULT (black diamond)
Pacific Crest



Rating = EASY (green circle)
Thunderbolt



Rating = DIFFICULT (black diamond)