minutes (1:20) on the inner scale. Read the fuel burn on the outer scale. 11.3 gallons. Exercise 3: Wind Correction (The Wind Side)

This uses the ratio side of the E6B (the "calculator" side).

The calculator side of the E6B operates on a 60:1 ratio, using the (a large black triangle on the inner scale) to represent speed in units per hour. Problem A: Calculating Time En Route (ETE)

Forgetting to convert minutes to hours (e.g., using 20 min as 0.333 hr).

You need to multiply $15 \times 3$.