Answer:
P = $1664.12 pay with 9% compounded monthly 
P = 1652.98 pay with 9% compounded continuously 
Step-by-step explanation:
given data 
time period = 20 year 
amount = $10000 
solution
we get here compound interest for 9% compounded monthly that is express as
FV = 
 .................1
here P is principal amount and r is interest rate and n compound in year and FV is future value 
$10000 = 
 
solve it we get 
P = $1664.12 pay with 9% compounded monthly 
and 
for 9% compounded continuously
 FV = 
 ............2
$10000 = P\times e^{0.09\times 20}
solve it we get 
P = 1652.98 pay with 9% compounded continuously