Question

At what speed do a bicycle and its rider, with a combined mass of 100 kg, have the same momentum as a 1400 car traveling at 6.0 ?

Answer 1

You need to provide units for the 6.0 speed. I assume the units of the car's mass (1400) are also kg.

Anyway, require that they both have the same M*V product. Then solve for the velocity of the bike & rider