“Help me and let me help you.” Or in Ghana’s Twi language: “Boa me na me mmoa wo.” The aphorism signifies cooperation and interdependence. And like many Twi expressions, it can be communicated with a ...

Mathematics has the potential to be a great equalizer. Compared with other scientific and technical fields, it requires few expensive physical resources. Sometimes, a whiteboard and a marker are all ...

You all know the score. A train leaves one city travelling at 35 miles per hour and another races toward it at 25 miles an hour from a city 60 miles away. How long do they take to meet in the middle?