document.write( "Question 1160871: it is estimated that the population of a village increases by 10 percent every five years. if the population of the village is 150,000 this year, what will be the estimated population ten years from now? \n" ); document.write( "
Algebra.Com's Answer #784274 by Theo(13342)![]() ![]() You can put this solution on YOUR website! the population increases by 10% evey five yhears. \n" ); document.write( "f = p * (1 + r) ^ n \n" ); document.write( "f is the future value \n" ); document.write( "p is the presnt value \n" ); document.write( "r is the interest rate per time period \n" ); document.write( "n is the number of time periods. \n" ); document.write( "the time periods are every 5 years. \n" ); document.write( "the formula becomes: \n" ); document.write( "f = 150,000 * (1 + .10) ^ 2 \n" ); document.write( "solve for f to get: \n" ); document.write( "f = 181,500. \n" ); document.write( "that's your solution. \n" ); document.write( "in 10 years, there are 2 five year periods, therefore n = 2. \n" ); document.write( "if you wanted to solve for the annual growth rate in this problem, you would do the following. \n" ); document.write( "p = 1 \n" ); document.write( "f = 1.10 \n" ); document.write( "r = (1 + r) \n" ); document.write( "n = 5 \n" ); document.write( "formula becomes: \n" ); document.write( "1.1 = 1 * (1 + r) ^ 5 \n" ); document.write( "this becomes 1.1 = (1 + r) ^ 5 \n" ); document.write( "take the fifth root of both sides of this equation to get: \n" ); document.write( "1.1 ^ (1/5) = 1 + r \n" ); document.write( "subtract 1 from both sides of this equaation to0 get: \n" ); document.write( "1.1 ^ (1/5) - 1 = r \n" ); document.write( "solve for r to get: \n" ); document.write( "r = .0192448765. \n" ); document.write( "that's the annual growth rate. \n" ); document.write( "with your time periods in years, rather than every 5 years, f = 150,000 * (1 + .0192448765) ^ 10 gets you: \n" ); document.write( "f = 181,500. \n" ); document.write( "same answer, as it should be if you did everything correctly.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |