Surprisingly enough, the letters in the following addition sum represent the digits 1 ... 9. If A=3 and D=2, what number is represented by "CAYLEY"?
The words are the names of three famous mathematicians. What countries did these mathematicians come from, when did they live and what is the main thing that are they famous for? There are many good websites about the history of mathematics where you can find the answers to these questions. For example, Google gives you a large number of links if you search for " history of maths ".