True course (TC) = 090°, TAS = 120 kt, Wind = 045° at 25 kt
You don't need 3 hours. You need 15 minutes a day. To get results, use the "Spaced Repetition" method. e6b flight computer exercises better
Using an E6B manually forces you to visualize the wind triangle. Every time you solve for wind correction angle (WCA) or ground speed (GS), you are constructing a mental model of how the air mass is moving your aircraft. True course (TC) = 090°, TAS = 120