The formulas of downwind and headwind are downwind speed = wind speed+static speed, and headwind speed = wind speed-static speed. Travel problem is an application problem that reflects the uniform motion of objects, some of which involve the motion of one object and some involve the motion of two objects.

Wind speed refers to the speed at which air moves relative to a fixed position on the earth.

Wind speed can only be graded if there is no grade, and wind speed is the basis for wind grading.

The wind speed formula in the first volume of the seventh grade of People's Education Edition is:

Downwind speed = windless speed+wind speed, headwind speed = windless speed-wind speed, which is a kind of application problem of one-dimensional linear equation in the third chapter of the first volume of the seventh grade, and it is the same as sailing in the water. The downstream sailing speed of the ship = still water speed+current speed, and the upstream sailing speed = still water speed-current speed.