Question
Xuan and Sean have a bicycle race. Xuan cycles at a speed of 18 km/h. Sean cycles at a speed of 21 km/h. If Sean lets Xuan start 40 min before him, how long will Sean take to catch up with Xuan?
3 m

Click button first when a symbol is required. X

Xuan and Sean have a bicycle race. Xuan cycles at a speed of 18 km/h. Sean cycles at a speed of 21 km/h. If Sean lets Xuan start 40 min before him, how long will Sean take to catch up with Xuan?