Age in a square year

The mathematician Augustus De Morgan liked to say that he was xx years old in the year x2x^2. He died in 18711871. Assuming nobody lives past 120120 years, what is xx?

Show hints (2)+
  1. Being xx in year x2x^2 means he was born in year x2xx^2-x.
  2. Find a perfect square x21871x^2 \le 1871 giving a lifespan under 120120. Try xx in the low 4040s.

Answer

Reveal answer →

43

Want the full step-by-step worked solution? It's part of Premium - along with a worked solution for every question in the bank.

Asked at: Jane Street, Citadel

Related questions