Your grandfather is retiring at the end of next year. He would like to ensure that his heirs receive payments of $$8,400$ a year forever, starting when he retires. If he can earn $7\mathrm{.}10$ percent annually, how much does your grandfather need to invest to produce the desired cash flow? $($Round answer to $2$ decimal places, e$.$g$.15\mathrm{.}25.)$

Present value of investment

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