What is the speed of passenger plane on runway before take off?

The speed at which an aircraft takes off is called Vr (r is rotation or take off), this is the minimum speed at which an aircraft develops sufficient lift and can safely take off. The Vr is chosen by a pilot after considering several parameters such as - Outside Air Temperature, Density, Runway Length Available, Gross Weight of the Aircraft, Presence or absence of any obstacle upon take off etc. Each aircraft has its own band of Vr. Small air crafts such as a Cessna 172 can take off anywhere between 55 Knots to 65 Knots. (one knot is 1.15 mile). Commercial airliners take off at various speed ranging from 120 mph to as high as 240 mph.