The Jinkōki of Yoshida Mitsuyoshi

Yoshida Mitsuyoshi (1598–1672) published the Jinkōki first in 1627. This was a problem book of elementary mathematics for everyday use but it also contained many interesting problems which attracted readers. This book became so popular that there have been more than 300 versions published during the Edo era (1603–1868) in Japan. In these notes, we shall survey the first edition of the Jinkōoki, and the problems which were added in later editions.