document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1083546>Question 1083546</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A population of bacteria originates with 2,000 bacteria. After a harmful substance is introduced into the environment, the rate of decline of the bacteria population is 2% per hour. In addition, 35 bacteria are added to the population each hour. How many bacteria are in the population after two hours (round your answer to the nearest whole number)?\r<BR>\n" );
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document.write( "A) 1,995<BR>\n" );
document.write( "B) 1,925<BR>\n" );
document.write( "C) 1,852<BR>\n" );
document.write( "D) 1,990 </SPAN>\n" );
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document.write( "Answer: <font color=red>Choice D) 1,990</font><BR>\n" );
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document.write( "Explanation:\r<BR>\n" );
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document.write( "During the first hour, the population declines by 2%<BR>\n" );
document.write( "New population = (old population) - (2% of old population)<BR>\n" );
document.write( "New population = (2000) - (2% of 2000)<BR>\n" );
document.write( "New population = (2000) - (0.02*2000)<BR>\n" );
document.write( "New population = 2000 - 40<BR>\n" );
document.write( "New population = 1960\r<BR>\n" );
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document.write( "After one hour, we go from 2000 bacteria to 1960 bacteria. \r<BR>\n" );
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document.write( "But we add in an additional 35 new members: <BR>\n" );
document.write( "New population = (old population) + 35<BR>\n" );
document.write( "New population = 1960 + 35<BR>\n" );
document.write( "New population = 1995\r<BR>\n" );
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document.write( "At the end of the first hour, the population is 1995.\r<BR>\n" );
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document.write( "In the second hour, the population declines by another 2%<BR>\n" );
document.write( "New population = (old population) - (2% of old population)<BR>\n" );
document.write( "New population = (1995) - (2% of 1995)<BR>\n" );
document.write( "New population = 1995 - 0.02*1995<BR>\n" );
document.write( "New population = 1995 - 39.9<BR>\n" );
document.write( "New population = 1955.1\r<BR>\n" );
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document.write( "So roughly 1955 individuals remain after the 2% decay\r<BR>\n" );
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document.write( "But we add in an additional 35 new members: <BR>\n" );
document.write( "New population = (old population) + 35<BR>\n" );
document.write( "New population = 1955 + 35<BR>\n" );
document.write( "New population = <font color=red>1990</font>\r<BR>\n" );
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document.write( "We are done because the second hour is over.<BR>\n" );
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