*Shinpen jinkoki* (1689) is a basic mathematics text originally written by Yoshida Mitsuyoshi (1598-1673) in 1627. The title page bears his seal:

Work using elementary operations is explained and illustrated with examples. A reader familiar with traditional Chinese/Japanese numerical notation can attempt to decipher the problem contents:

Area computation for common geometric shapes is taught:

See images from another copy of *Shinpen jinkoki* here in *Convergence* and in the exhibit described below.

*The images above are presented through the kind cooperation of the National Diet Library, Japan, and are used with permission. They were obtained from the library’s digital gallery exhibit, Japanese Mathematics in the Edo Period, where a complete examination and viewing of the item presented above can be found. *