Mathematics - Ratios and Proportions - Solving proportions - Map Scale Mystery

Show a map with scale '1 cm = 50 km'. Two cities are 3.5 cm apart on the map. 'How far apart are they in real life?' Options: 150 km, 175 km, 200 km, 350 km. Do 4 scale/proportion problems: map distances, model cars, recipe scaling, shadow/height problems. Students set up proportions intuitively.