document.write( "Question 1100944: The repair department of the bicycle shop repairs three things: flat tires, bent handle bars and
\n" ); document.write( "ripped seats. Today in the repair department, 25% of the bikes had flat tires only, 5% had bent
\n" ); document.write( "handlebars only, and 10% had ripped seats only. Just 1/12th of the bikes had all three repairs to
\n" ); document.write( "do: flat tires, bent handlebars and ripped seats. No bikes were completely fixed and there are a
\n" ); document.write( "total of 101 repairs to be made. How many bikes are in the repair department? How many bikes
\n" ); document.write( "need two repairs? If less than half of all the bikes have a ripped seat, what is the range of bikes
\n" ); document.write( "that need both the tires and handlebars repaired without needing to fix the seat?
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Algebra.Com's Answer #715526 by KMST(5328)\"\" \"About 
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ONE APPROACH:
\n" ); document.write( "\"N\"= number of bikes in the shop waiting to be repaired.
\n" ); document.write( "Of those,
\n" ); document.write( "25% have flat tires only,
\n" ); document.write( "5% have bent handlebars only, and
\n" ); document.write( "10% have ripped seats only.
\n" ); document.write( "That adds up to 25%+5%+10%=40% .
\n" ); document.write( "So, the number of bikes needing only 1 repair is
\n" ); document.write( "\"%2840%2F100%29N=%282%2F5%29N\" .
\n" ); document.write( "The number of bikes needing 3 repairs is \"%281%2F12%29N\" .
\n" ); document.write( "The rest of the bikes is the fraction of all bikes that need exactly 2 repairs.
\n" ); document.write( "As a fraction of all the bikes, that is
\n" ); document.write( "\"1-2%2F5-1%2F12=60%2F60-24%2F60-5%2F60=31%2F60\" .
\n" ); document.write( "As a number of bikes, it is
\n" ); document.write( "\"N-%282%2F5%29N-%281%2F12%29N=%281-2%2F5%2F1%2F12%29N=%2831%2F60%29N\" .
\n" ); document.write( "Counting the number of repairs needed, we have
\n" ); document.write( "\"%282%2F5%29N\" repairs for the \"%282%2F5%29N\" bikes that need only 1 repair,
\n" ); document.write( "\"2%2831%2F60%29N=%2831%2F30%29N\" repairs for the \"%2831%2F60%29N\" bikes that need exactly 2 repairs,
\n" ); document.write( "and
\n" ); document.write( "\"3%281%2F12%29N=%281%2F4%29N\" repairs for the \"%281%2F12%29N\" bikes that need 3 repairs.
\n" ); document.write( "The number of repairs adds up to
\n" ); document.write( "\"%282%2F5%29N%2B%2831%2F60%29N%2B%281%2F4%29N=101\"
\n" ); document.write( "\"%282%2F5%2B31%2F60%2B1%2F4%29N=101\"
\n" ); document.write( "\"%2824%2F60%2B31%2F60%2B15%2F60%29N=101\"
\n" ); document.write( "\"%28101%2F60%29N=101\"
\n" ); document.write( "\"%2860%2F101%29%28101%2F60%29N=%2830%2F101%29101\"
\n" ); document.write( "\"highlight%28N=60%29\"
\n" ); document.write( "There are \"highlight%2860%29\" bikes in the repair department.
\n" ); document.write( "
\n" ); document.write( "Of those \"60\" bikes,
\n" ); document.write( "\"%2831%2F60%2960=highlight%2831%29\" need exactly two repairs,
\n" ); document.write( "\"1%2F12\" , or \"5\" bikes, need all 3 repairs including their ripped seats,
\n" ); document.write( "25% , or \"15\" bikes, only need flat tires fixed,
\n" ); document.write( "5% , or \"3\" bikes, only need bent handlebars fixed, and
\n" ); document.write( "10%, or \"6\" bikes only need their ripped seats fixed.
\n" ); document.write( "In pictures, we could represent is as
\n" ); document.write( " .\r
\n" ); document.write( "\n" ); document.write( "The last question asks for the range of values for value of \"x\" ,
\n" ); document.write( "The number of \"bikes
\n" ); document.write( "that need both the tires and handlebars repaired without needing to fix the seat\".
\n" ); document.write( "
\n" ); document.write( "From the picture,
\n" ); document.write( "if \"%22%3F%22%2B%22%3F%22=0\" , \"x=60-6-5-15-3=31\" is the greatest possible \"x\" ;
\n" ); document.write( "If \"6%2B5%2B%22%3F%22%2B%22%3F%22=29\" , \"x=60-29-15-3=13\" is the least possible \"x\" .
\n" ); document.write( "
\n" ); document.write( "Without a picture:
\n" ); document.write( "If \"R\" is the total number of ripped seat repairs,
\n" ); document.write( "we do not know \"R\" exactly, but
\n" ); document.write( "it includes at least the \"6\" that need only the seat repaired,
\n" ); document.write( "and the \"5\" that need all 3 repairs, so
\n" ); document.write( "\"R%3E=6%2B5\" or \"11%3C=R\" .
\n" ); document.write( "If less than half the bikes have a ripped seat
\n" ); document.write( "(meaning \"29\" or less bikes),
\n" ); document.write( "we also know that \"R%3C=29\" , so
\n" ); document.write( "\"11%3C=R%3C=29\" .
\n" ); document.write( "
\n" ); document.write( "If we exclude
\n" ); document.write( "those \"R\" bikes with ripped seats,
\n" ); document.write( "the \"15\" bikes that only need flat tires fixed,
\n" ); document.write( "and the \"3\" bikes that only need bent handlebars fixed,
\n" ); document.write( "we are excluding \"R%2B15%2B3=R%2B18\" ,
\n" ); document.write( "what is left is the group of bikes that needs
\n" ); document.write( "\"both the tires and handlebars repaired without needing to fix the seat.\"
\n" ); document.write( "That number is \"x=60-%28R%2B18%29=60-R-18=42-R\" .
\n" ); document.write( "As \"11%3C=R%3C=29\" ,
\n" ); document.write( "\"42-11%3E=42-R%3E=42-29\"
\n" ); document.write( "\"31%3E=x%3E=13\" .
\n" ); document.write( "There are at least \"13\" and at most \"31\" bikes that need
\n" ); document.write( "\"both the tires and handlebars repaired without needing to fix the seat.\"
\n" ); document.write( "The range can be expressed as [13,31], or as \"13%3C=x%3C=31\"
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