Question 270853
If the 2% interest on the principle is
reinvested each year,
{{{A = P*(1 + t*r)}}}
{{{A = 400 + 8000}}}
{{{P = 8000}}}
{{{r = .02}}}
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{{{8400 = 8000*(1 + t*.02)}}}
{{{8400/8000 = 1 + .02t}}}
{{{.02t = 1.05 - 1}}}
{{{.02t = .05}}}
{{{t = 2.5}}}
The $8000 must be invested for 2.5 years