document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1189949>Question 1189949</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A water jug with a capacity of 20 gallons is 20 percent full. At the end of every third day, water is added to the jug. If the amount of water added is equal to 50 percent of the water in the jug at the beginning of that day, how many days does it take for the jug to be at least 85% full? <BR>\n" );
document.write( "A)4   B)4   C)12   D)15   E)20 </SPAN>\n" );
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document.write( "20% of 20 gallons is 4 gallons.  So you start with 4 gallons in the jug.<br><BR>\n" );
document.write( "The amount added every third day is half the amount in the jug at the beginning of that day; that means the amount in the jug is multiplied by 1.5.  So<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%281.5%29%5Ex=20 ALIGN=MIDDLE  ALT=\"4%281.5%29%5Ex=20\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1.5%5Ex=5 ALIGN=MIDDLE  ALT=\"1.5%5Ex=5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "Use logarithms, or a graphing calculator....<br><BR>\n" );
document.write( "Or...<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1.5+=+3%2F2 ALIGN=MIDDLE  ALT=\"1.5+=+3%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1.5%5Ex=%283%2F2%29%5Ex ALIGN=MIDDLE  ALT=\"1.5%5Ex=%283%2F2%29%5Ex\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%283%2F2%29%5E4+=+81%2F16+=+5.0625 ALIGN=MIDDLE  ALT=\"%283%2F2%29%5E4+=+81%2F16+=+5.0625\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "That is slightly more than what we need; so adding more water to the jug 4 times will fill the jug.<br><BR>\n" );
document.write( "And since water is added to the jug every third day, the number of days it takes to fill the jug is 4*3=12.<br><BR>\n" );
document.write( "ANSWER: C)12<br>\r<BR>\n" );
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