Question 1029330
Let {{{ r }}} = the rate of inflation
{{{ 40000 = 20000*( 1 + r )^8 }}}
{{{ ( 1 + r )^8 = 2 }}}
Take the log of both sides
{{{ 8*log( 1 + r ) = log(2) }}}
{{{ log( 1 + r ) = log(2) / 8 }}}
{{{ log( 1 + r ) = .30103/8 }}}
{{{ log( 1 + r ) = .03763 }}}
{{{ 1 + r = 10^.03763 }}}
{{{ 1 + r = 1.0905 }}}
{{{ r= .0905 }}}
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Let {{{ p }}} =  the price of the car in 5 years
{{{ p = 20000*( 1.0905 )^5 }}}
{{{ p = 20000*1.5422 }}}
{{{ p = 30843.12 }}}
The price will be $30,843.12 in 5 yrs