Mathematical
The wooden box without cover is equipped with PVC number cards 1-9000, thousands of bits 22*7, hundreds of bits 16.5*7, tens of bits 11*7, and units bits 7*5.5
The wooden box without cover is equipped with PVC number cards 1-9000, thousands of bits 22*7, hundreds of bits 16.5*7, tens of bits 11*7, and units bits 7*5.5
