document.write( "Question 1005061: A city bus finishes its 96 mile route in the same amount of time that a rural bus finishes its 144 mile route. The city bus averages 18 mph slower than the rural bus. How long does it take each bus to finish its route?
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Algebra.Com's Answer #621395 by Theo(13342)\"\" \"About 
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rate * time = distance.\r
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\n" ); document.write( "\n" ); document.write( "city bus distance = 96 miles.
\n" ); document.write( "rural bus distance = 144 miles.\r
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\n" ); document.write( "\n" ); document.write( "city bus rate = 18 mph less than the rural bus rate.\r
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\n" ); document.write( "\n" ); document.write( "assume the rural bus rate is x miles per hour.
\n" ); document.write( "the city bus rate is therefore x - 18\r
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\n" ); document.write( "\n" ); document.write( "for the city bus:\r
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\n" ); document.write( "\n" ); document.write( "rate * time = distance becomes (x-18) * time = 96\r
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\n" ); document.write( "\n" ); document.write( "for the rural bus:\r
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\n" ); document.write( "\n" ); document.write( "rate * time = distance becomes x * time = 144\r
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\n" ); document.write( "\n" ); document.write( "time is the same for both.\r
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\n" ); document.write( "\n" ); document.write( "we'll solve each equation for time to get:\r
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\n" ); document.write( "\n" ); document.write( "time = 96 / (x-18) for the city bus.\r
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\n" ); document.write( "\n" ); document.write( "time = 144 / x for the rural bus.\r
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\n" ); document.write( "\n" ); document.write( "we replace time in the second equation with the equivalent value for time in the first equation to get:\r
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\n" ); document.write( "\n" ); document.write( "96 / (x-18) = 144 / x\r
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\n" ); document.write( "\n" ); document.write( "we multiply both sides of the equation by (x-18) * x to get:\r
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\n" ); document.write( "\n" ); document.write( "x * (x-18) * 96 / (x-18) = x * (x-18) * 144 / x\r
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\n" ); document.write( "\n" ); document.write( "we simplify to get:\r
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\n" ); document.write( "\n" ); document.write( "x * 96 = (x-18) * 144\r
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\n" ); document.write( "\n" ); document.write( "we simplify further to get:\r
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\n" ); document.write( "\n" ); document.write( "x * 96 = 144 * x - 18 * 144\r
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\n" ); document.write( "\n" ); document.write( "we simplify further to get:\r
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\n" ); document.write( "\n" ); document.write( "96x = 144x - 2592\r
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\n" ); document.write( "\n" ); document.write( "we subtract 96x from both sides of this equation and add 2592 to both sides of this equation to get:\r
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\n" ); document.write( "\n" ); document.write( "2592 = 144x - 96x\r
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\n" ); document.write( "\n" ); document.write( "we simplify to get:\r
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\n" ); document.write( "\n" ); document.write( "2592 = 48x\r
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\n" ); document.write( "\n" ); document.write( "we divide both sides of this equation by 48 to get:\r
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\n" ); document.write( "\n" ); document.write( "2592 / 48 = x\r
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\n" ); document.write( "\n" ); document.write( "we solve for x to get:\r
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\n" ); document.write( "\n" ); document.write( "x = 54\r
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\n" ); document.write( "\n" ); document.write( "that's the rate of the rural bus.\r
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\n" ); document.write( "\n" ); document.write( "the rate of the city bus is 18 mph less than that.\r
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\n" ); document.write( "\n" ); document.write( "the rate of the city bus is 54 - 18 = 36 mph.\r
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\n" ); document.write( "\n" ); document.write( "the rural bus travels at 54 mph.
\n" ); document.write( "the city bus travels at 36 mph.\r
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\n" ); document.write( "\n" ); document.write( "if we did this correctly, time should be the same for both buses.\r
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\n" ); document.write( "\n" ); document.write( "for the city bus, the formula is 36 * time = 96 miles
\n" ); document.write( "solve for time to get time = 96 / 36 = 8/3 hours.\r
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\n" ); document.write( "\n" ); document.write( "for the rural bus, the formula is 54 * time = 144 miles
\n" ); document.write( "solve for time to get time = 144 / 54 = 8/3 hours.\r
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\n" ); document.write( "\n" ); document.write( "time is the same for both so we're done.\r
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\n" ); document.write( "\n" ); document.write( "they asked for how long each bus took to finish its route.\r
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\n" ); document.write( "\n" ); document.write( "the solution is that each bus took 8/3 hours to finish its route.\r
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\n" ); document.write( "\n" ); document.write( "this is equivalent to 2 and 2/3 hours.\r
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\n" ); document.write( "\n" ); document.write( "as a bonus, we also figured out how fast each bus was traveling.\r
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\n" ); document.write( "\n" ); document.write( "the city bus was traveling at 36 miles per hour.
\n" ); document.write( "the rural bus was traveling at 54 miles per hour.\r
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