111.--REAPING THE CORN.

The whole field must have contained 46.626 square rods. The side of the

central square, left by the farmer, is 4.8284 rods, so it contains

23.313 square rods. The area of the field was thus something more than a

quarter of an acre and less than one-third; to be more precise, .2914 of

an acre.

Amusements in Mathematics · 第 617 / 970 题