Randall is making monthly contributions of of $$430$ to his savings account which pays interest at the APR of $5\mathrm{.}9\%,$ compounded monthly. Right after Randall makes his $69$ th contribution, the bank changes the APR to $9\mathrm{.}5\%$ and Randall makes $43$ more $$430$ contributions. What is Randall's balance right after his last contribution?

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