document.write( "Question 404453: Depreciation on a car can be determined by the formula V=C(1-r)^t , where V is the value of the car after t years, C is the original cost, and r the rate of depreciation. If a car's cost, when new, is $15,000, the rate of depreciation is 30%, and the value of the car now is $3,000, how old is the car to the nearest tenth of a year? \n" ); document.write( "
Algebra.Com's Answer #285867 by lwsshak3(11628)\"\" \"About 
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Depreciation on a car can be determined by the formula V=C(1-r)^t , where V is the value of the car after t years, C is the original cost, and r the rate of depreciation. If a car's cost, when new, is $15,000, the rate of depreciation is 30%, and the value of the car now is $3,000, how old is the car to the nearest tenth of a year?
\n" ); document.write( "..
\n" ); document.write( "V=C(1-r)^t
\n" ); document.write( "3000=15000(1-.3)^t
\n" ); document.write( "3000=15000(.7)^t
\n" ); document.write( "3000/15000=(.7)^t
\n" ); document.write( "1/5 =(.7)^t
\n" ); document.write( ".2=.7^t
\n" ); document.write( "using logarithms to solve
\n" ); document.write( "log.2 = t*log.7
\n" ); document.write( "t=log.2/log.7
\n" ); document.write( "t=4.51 years
\n" ); document.write( "ans:
\n" ); document.write( "The car is 4.51 years old\r
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