Assertion: abacus's deck | /r/HasProperty | replaced by soroban abacus
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Source sentences:
text: The Suanpan, one of the modern age abaci which was a Chinese abacus had 2/5 decks and due to its complexity was replaced by Soroban abacus, a Japanese abacus, which was developed further by a famous mathematician Seki Kowa who removed one bead each from upper and lower decks to make it 1/4 decks.