document.write( "Question 1039797: You buy a commemorative coin for $20. The value of the coin increases at a rate of 3.5% per year. \r
\n" ); document.write( "\n" ); document.write( "How much will the coin be worth in 15 years?\r
\n" ); document.write( "\n" ); document.write( "After how many years will the coin have doubled in value? \n" ); document.write( "

Algebra.Com's Answer #654553 by Aldorozos(172) $\"\"$ $\"About$

You can put this solution on YOUR website!
Go to google.com and type future value to understand what it is. Also learn about future value calculator to see how it works
\n" ); document.write( "The present value is 20
\n" ); document.write( "The rate is .035
\n" ); document.write( "The period is 15
\n" ); document.write( "Here is the formula
\n" ); document.write( "F=p(1+r)^n
\n" ); document.write( "P=20
\n" ); document.write( "R=.o35
\n" ); document.write( "N=15
\n" ); document.write( "Using calculator we calculate f which is the future value
\n" ); document.write( "F is around $33.50\r
\n" ); document.write( "\n" ); document.write( "If it is doubled then
\n" ); document.write( "40=20(1.035)^n
\n" ); document.write( "Here we have to calculate n which is the number of years. Dividing both sides by 20 we get
\n" ); document.write( "2=(1.035)^n
\n" ); document.write( "Using log
\n" ); document.write( "Log2 = log (1.035)^n
\n" ); document.write( "Log2=nlog (1.035)
\n" ); document.write( "We use calculator to find the two logs and we get n=20.
\n" ); document.write( "This means after 20 years the coin would worth $40
\n" ); document.write( "You have to learn how log works \n" ); document.write( "

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