Not correct david, the reserve bank does not lend money to banks. Banks receive the majority of their funds from deposits, which in turn they use to fund loans. You'll see majority of term deposits are around 5-5.5%, with variable interest home loan rates at about 6.7%, in this instance meaning the return for the bank is around 1.5%.
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http://moneybasics.nab.com.au/how-banks-work-96.html
