When selecting a fuse for a motor, what is the exact method for calculating the 'inrush current' to ensure the power stays on when the machine first starts up?

Motors need a huge burst of extra energy to start spinning from a dead stop. This quick spike of power is called inrush current. It is like pushing a heavy car; you need a giant shove to get it moving, but once it is rolling, you only need a little push to keep it going. To find the right fuse, you first look at....