Arithmetic on today's supply, not a forecast. It assumes nothing about whether Cardano could attract that much money.
A coin's market capitalisation is its price multiplied by the number of coins in circulation. Cardano has 36,696,309,409 ADA in circulation at $0.2074 each, which is $7.61B. Holding that supply still and putting Ethereum's $306.63B in its place gives $8.3558 per ADA.
Cardano would have to take on $299.02B of new money to get there. A 40.3x move is large: it happens, and it usually needs the whole market to grow instead of one coin to take share from another.
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 ADA at that level, which is the part that actually decides a price.
$8.3558 per ADA. That is Ethereum's current market capitalisation of $306.63B divided across the 36,696,309,409 ADA in circulation.
40.3x. Cardano trades at $0.2074 today and Ethereum's market cap is $306.63B against Cardano's $7.61B.
No. It is one division: Ethereum's market capitalisation spread over the supply of ADA that exists today. It assumes nothing about whether Cardano 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 $306.63B of market cap spread over more coins gives a lower price per coin. This uses the 36,696,309,409 ADA in circulation now.