暗算

Meaning

1. nvsvt
   mental arithmetic

Example sentences

• 彼は暗算をするほど頭が良くない。

  He doesn't have enough brains to do sums in his head.

• 彼は暗算が出来るほど頭が良くない。

  He doesn't have enough brains to do sums in his head.

• 彼は暗算が出来るほどの頭脳を持ち合わせていない。

  He doesn't have enough brains to do sums in his head.