document.write( "Question 1054139: please help me to solve this problem.\r
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document.write( "During a certain week, a small wind generator and a small hydro unit together produce 5880 kWh, with the wind generator operating only 85.0% of the time. During another week, the two units produce 6240 kWh, with the wind generator working 95.0% of the time and the hydro unit down 7.50 h for repairs. Assuming that each unit has a constant output when operating, find the number of kilowatts produced by each in 1.00 h.\r
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document.write( "Do not round intermediate results. Round only final answers. Round to the nearest integer.\r
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document.write( "wind generator:
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document.write( "hydro unit: \n" );
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Algebra.Com's Answer #669373 by Theo(13342)![]() ![]() You can put this solution on YOUR website! assuming that these operate 24 hours a day and that there are 7 days in a week, then the total number of hours each is up, if they are up 100% of the time, will be 7 * 24 = 168 hours.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "based on that assumption.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "85% of the time will be .85 * 168 = 142.8 hours. \n" ); document.write( "95% of the time will be .95 * 168 = 159.6 hours.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the general formula is rate * time = quantity of work produced.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the quantity of work produces is in kilowatt hours. \n" ); document.write( "the time is in hours. \n" ); document.write( "the rate will be in kilowatt hours per hour.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "let w = the rate of the wind generator. \n" ); document.write( "let h = the rate of the hydro unit.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "for the first week, you get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "142.8 * w + 168 * h = 5880\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "for the second week, you get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "159.6 * w + (168 - 7.5) * h = 6240.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "this can be simplified to 159.6 * w + 160.5 * h = 6240\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you have 2 equations that need to be solved simultaneously.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "they are:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "142.8 * w + 168 * h = 5880 \n" ); document.write( "159.6 * w + 160.5 * h = 6240\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "assuming that you know how to solve equations simultaneously, i'll jump to the answer to tell you that the simultaneous solution to these equation is:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "w = 26.86084142 kilowatts per hour. \n" ); document.write( "h = 12.16828479 kilowatts per hour.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "your solution is that the wind generator generates 27 kilowatts per hour and the hydro unit generates 12 kilowatts per hour.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "i also solved this graphically as shown below. \n" ); document.write( "look for the intersection between the lines of the two equations. \n" ); document.write( "the coordinate point of the intersection confirms the solution. \n" ); document.write( "in the graph, x represents w and y represents h.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " ![]() \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "you can confirm the solution is correct, by replacing w with 26.86084142 and h with 12.16828479 in the following equations.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "142.8 * w + 168 * h = 5880 \n" ); document.write( "159.6 * w + 160.5 * h = 6240\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "if my assumptions about the number of hours in a week being equal to 168, then i believe this solution is correct.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "check it out and see if you think that this is reasonable.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |