Join Sir Cumference, Lady Di of Ameter, and their son Radius for wordplay, puns, and problem solving in this angle-packed math adventure. In the third installment of the beloved Sir Cumference series, Radius must prove himself on his quest for knighthood by rescuing a king.

Sent off with the family medallion for luck, Radius dodges dangers and dragons. The ultimate challenge lies in a mysterious castle with a maze of many angles. With a medallion at the back of the book readers can jump in the adventure and help Radius find the right angle.


在這個充滿角度的數學冒險中加入Aum的Cumference爵士和他們的兒子Radius的文字遊戲，雙關語和問題解決。 在心愛的Sir Cumference系列的第三部中，Radius必須通過拯救國王來證明自己對騎士的追求。

送出家庭獎章以求運氣，Radius避開危險和龍。 最終的挑戰在於一個神秘的城堡，有許多角度的迷宮。 在書的後面有一個獎章，讀者可以跳進冒險並幫助Radius找到合適的角度。

（文字整理/徐琍沂&劉世明）