"The Book That Allows Elementary School Students to Perfectly Do 19x19 Mental Calculation in Just One Day" Price: 1100 yen #Book I bought this at a bookstore for my child, but they only looked through it and didn't use it at all, so I'm selling it. I'm sorry, but I can't offer a discount or reserve this item. Shipping is planned via Yu-Packet Post, but it may be changed to Rakuraku Mercari Delivery.