A little more than a year ago, on a trip to Nairobi, Kenya, some colleagues and I met a 12-year-old Masai boy named Richard Turere, who told us a fascinating story. His family raises livestock on the ...

To draw a pie chart, we need to represent each part of the data as a proportion of 360, because there are \(360^{\circ}\) in a circle. For example, if 55 out of 270 vehicles are vans, we will ...