John D. Cook wrote an interesting blog post on mentally multiply by π should you not have access to a calculator. As someone who remembers π to 11 decimal places and used it as a chat-up line once (it kinda worked), this resonated with me.
John D. Cook wrote an interesting blog post on mentally multiply by π should you not have access to a calculator. As someone who remembers π to 11 decimal places and used it as a chat-up line once (it kinda worked), this resonated with me.