Longitude and latitude
The teacher of the Earth Science class was lecturing on map reading.
He spent the class explaining about latitude, longitude, degrees, and minutes. Towards the end of class, the teacher asked his students, "Suppose I asked you to meet me for lunch at 23 degrees, 4 minutes north latitude and 45 degrees, 15 minutes east longitude..."
A student's voice broke the confused silence, and volunteered, "I guess you'd be eating alone, sir."