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Alonzo plans to retire as soon as he has accumulated $250,000 through quarterly payments of $4,500. If Alonzo invests this money at 5.4% interest, compounded quarterly, how long (to the nearest year) until can he retire?

Find t=......years? the answer is not 300 months, 25 years or 75 years.

There is an example: Alonzo plans to retire as soon as he has accumulated $250,000 through quarterly payments of $2,000. If Alonzo invests this money at 5.4% interest, compounded quarterly, how long (to the nearest year) until can he retire? and the answer is 18 years so if you can solve this you can solve the problem above