15k units X $1000.
Float is something else, this is investing the deposit money and keeping it in play as long as possible before cutting the check. Float can be considered the time between cutting a check and the recipient's bank drawing the funds from the issuing bank.
Mailing checks on Friday is a regular occurrence as the checks will not make it back to issuer's bank before Monday.
Either way, If interest is calculated daily on the issuer's account they make more money. If it's paid on average daily balance, they make more money...
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