document.write( "Question 1071198: The relative growth rate for a certain type of bacteria population is 78% per hour. A small culture has formed and in just 5 hours the count shows to be 34,820 bacteria in the culture. What is the initial number of bacteria in the culture?\r
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Algebra.Com's Answer #686167 by Theo(13342)![]() ![]() You can put this solution on YOUR website! discrete compound growth rate formula is:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "f = p * (1+r)^n\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "f is the future value. \n" ); document.write( "p is the present value \n" ); document.write( "r is the growth rate per time period. \n" ); document.write( "t is the number of time periods.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the growth rate is 78% per hour = .78 \n" ); document.write( "the time period is hours.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "in 5 hours, there are 34,820 bacteria in the culture.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "formula becomes\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "34820 = p * 1.78^5\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "divide both sides of this equation by 1.78^5 and solve for p to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "p = 34820 / 1.78^5 = 1948.627177\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "in 5 hours, 1948.627177 bacteria will have grown to be equal to 1948.627177 * 1.78^5 = 34820 bacteria.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |