Use the simple interest formula to find the unknown quantity. i = prt i = $9 p = $450 r = 4% t =

First, converting R percent to r a decimal
r = R/100 = 4%/100 = 0.04 per year,
then, solving our equation

t = 9 / ( 450 × 0.04 ) = 0.5
t = 0.5 years

The time required to
accumulate simple interest of $ 9.00
from a principal of $ 450.00
at an interest rate of 4% per year
is 0.5 years (about 0 years 6 months).