Arithmetic on today's supply, not a forecast. It assumes nothing about whether XRP could attract that much money.
A coin's market capitalisation is its price multiplied by the number of coins in circulation. XRP has 63,159,881,785 XRP in circulation at $1.2960 each, which is $81.86B. Holding that supply still and putting Cardano's $7.23B in its place gives $0.11450648 per XRP.
XRP is already worth more than Cardano. Moving to the smaller cap would take XRP down to $0.11450648, which is 0.088x of what it trades at now.
Supply is held still, and in practice it moves: coins are minted, burned and unlocked, and every one of those changes the price a given market capitalisation implies. The figure also says nothing about whether the money exists to buy XRP at that level, which is the part that actually decides a price.
$0.11450648 per XRP. That is Cardano's current market capitalisation of $7.23B divided across the 63,159,881,785 XRP in circulation.
0.088x. XRP trades at $1.2960 today and Cardano's market cap is $7.23B against XRP's $81.86B.
No. It is one division: Cardano's market capitalisation spread over the supply of XRP that exists today. It assumes nothing about whether XRP could attract that much money, and it holds the supply still when in practice supply changes.
It sets it. Market cap is price times circulating supply, so the same $7.23B of market cap spread over more coins gives a lower price per coin. This uses the 63,159,881,785 XRP in circulation now.