注目の話題: 初対面の人と仲良くなれません。; 同棲するなら1人になれる部屋が欲しいって言ったら号泣された; おばさんイジリされる職場

Science,English,and math 4th

No.374　21/04/21 15:34
燻し銀三 ( 60代 ♂ IJ7P0b ) あ+あ-

【Do you know an almighty pair of scales ?】

《Look for a false coin!》

...the answer is twice. You may have thought, only twice? The author expressed its concrete way like the next.

The first time, we choose six coins at random and put them on the both of the scales by every three coins. If they are balanced, the fake is either of the rest two. If the scale is leaned on the one side, the fake one is among the three on the scale which was leaned.

The second time. When being balanced, we put the rest of the two coins on the scale one by one, and the one is leaned, so it’s the fake.

共感2

最初

ふとした疑問掲示板のスレ一覧

ふとした疑問、普段気になっていたことなどをみんなで話そう❗

レス新
人気
スレ新
レス少

閲覧専用のスレを見る

新しくスレを作成する

サブ掲示板

注目の話題

カテゴリ一覧