document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1195305>Question 1195305</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Brown can plant his lettuces in an hour and a half.His <BR>\n" );
document.write( "son could plant them in two and a half hours.How<BR>\n" );
document.write( "long would it take them if they worked together? </SPAN>\n" );
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document.write( "1 and a half = 1 + 1/2 = 1.5<BR>\n" );
document.write( "2 and a half = 2 + 1/2 = 2.5\r<BR>\n" );
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document.write( "1.5*2.5 = 3.75\r<BR>\n" );
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document.write( "Let's say there are 375 plants of lettuce. <BR>\n" );
document.write( "I'm picking this number so that the division results of the next two paragraphs are whole numbers. <BR>\n" );
document.write( "The number is derived from moving the decimal point on 3.75 two spots to the right to arrive at 375.\r<BR>\n" );
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document.write( "Brown can plant all that lettuce in 1.5 hours if he works alone. <BR>\n" );
document.write( "His unit rate is 375/(1.5) = 250 plants per hour. <BR>\n" );
document.write( "The unit rate is found by dividing the number of plants over the time needed.<BR>\n" );
document.write( "Think of the formula distance = rate*time which rearranges into rate = distance/time. <BR>\n" );
document.write( "In this case, \"distance\" is the amount done, aka the amount planted.\r<BR>\n" );
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document.write( "The son can do the same job, when working alone, in 2.5 hours. The son's unit rate is 375/(2.5) = 150 plants per hour.\r<BR>\n" );
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document.write( "If the two work together without getting in each other's way, then their combined unit rate is 250+150 = 400 plants per hour.\r<BR>\n" );
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document.write( "x = number of hours they work together<BR>\n" );
document.write( "400x = amount planted<BR>\n" );
document.write( "400x = 375<BR>\n" );
document.write( "x = 375/400<BR>\n" );
document.write( "x = (15*25)/(16*25)<BR>\n" );
document.write( "x = 15/16<BR>\n" );
document.write( "x = 0.9375\r<BR>\n" );
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document.write( "Answer as a fraction = 15/16 of an hour<BR>\n" );
document.write( "Answer as a decimal = 0.9375 of an hour\r<BR>\n" );
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document.write( "If you wanted to convert to minutes, then,<BR>\n" );
document.write( "0.9375 hrs = 0.9375*60 = 56.25 min<BR>\n" );
document.write( "which further breaks down into<BR>\n" );
document.write( "56.25 min = 56 min + 15 sec<BR>\n" );
document.write( "because 15 seconds is 15/60 = 1/4 = 0.25 of a minute<BR>\n" );
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