Shoeseller and mathematician

A shoeseller meets a mathematician and complains that he does not know what size shoes to buy.  “No problem,” says the mathematician, “there is a simple equation for that,” and he shows him the Gaussian normal distribution.  The shoeseller stares some time at het equation and asks, “What is that symbol?” “That is the Greek letter pi.”  “What is pi?” “That is the ratio between the circumference and the diameter of a circle.”  Upon this the shoeseller cries out: “What does a circle have to do with shoes?!”

The Promising Phd Candidate

A promising PhD candidate was presenting his thesis at his final examination. He proceeded with a derivation and ended up with something like:

F = -MA

He was embarrassed, his supervising professor was embarrassed, and the rest of the committee was embarrassed. The student coughed nervously and said “I seem to have made a slight error back there somewhere.”

One of the mathematicians on the committee replied dryly, “Either that or an odd number of them!”