. Friends and acquaintances have said the young boy was a mathematical prodigy who could add large columns of numbers in his head, a talent he occasionally demonstrated in his later years. Warren often visited his father's stockbrokerage shop as a child, and chalked in the stock prices on the blackboard in the office. At 11 years old he made his first investment, buying three shares of Cities Service Preferred at $38 per share. The stock quickly dropped to only $27, but Buffett held on tenaciously until they reached $40. He sold his shares at a small profit, but regretted the decision when Cities Service shot up to nearly $200 a share. He later cited this experience as an early lesson in patience in investing.