document.write( "Question 261964: Jim,
\n" ); document.write( " I have tried to follow and plug in the equation but it is not working. I have been at this for over an hour and my brain is fried. Help!!\r
\n" ); document.write( "\n" ); document.write( "Bayside Insurance offers two health plans. Under plan A Giselle would have to pay the first $140 of her bills and 25% of the rest. Under plan B she would have to pay the first $160 of her bills and 20% of the rest. For what amount of medical bills will plan B save Giselle money? Assume she has over $160 in bills.\r
\n" ); document.write( "\n" ); document.write( "Giselle would save with plan B if she had more than $_________in bills?\r
\n" ); document.write( "\n" ); document.write( "When it says assume she has over $160 in bills, does that mean you can use any number higher than 160? \r
\n" ); document.write( "\n" ); document.write( "Please help,
\n" ); document.write( "Thank you
\n" ); document.write( "Deborah
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Algebra.Com's Answer #193054 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
The reason why we're assuming that she has over $160 in medical bills is if she had less than $160 in bills, then she would be clearly paying more for plan B. For instance, if she has $159 in bills, then she pays almost $15 more for plan B.\r
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\n" ); document.write( "\n" ); document.write( "Let x = amount Giselle has to pay (ie her bill)\r
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\n" ); document.write( "\n" ); document.write( "Under plan A, she has to pay the first $140 and then 25% of the rest. So if we assume that she has over $160 in bills, this means that \"x%3E160\". After she pays the initial $140, then she has 25% of \"x-140\" in bills left over. So this means that under plan A, the cost is \"c=140%2B0.25%28x-140%29\"\r
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\n" ); document.write( "\n" ); document.write( "Similarly, under plan B, because \"she would have to pay the first $160 of her bills and 20% of the rest\", this means that the cost for plan B is \"c=160%2B0.20%28x-160%29\"\r
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\n" ); document.write( "\n" ); document.write( "So to figure out when plan B will save her money, simply set the plan B expression less than the plan A expression\r
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\n" ); document.write( "\n" ); document.write( "\"Plan_B%3CPlan_A\"\r
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\n" ); document.write( "\n" ); document.write( "\"160%2B0.20%28x-160%29%3C140%2B0.25%28x-140%29\" Substitute the given cost equations.\r
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\n" ); document.write( "\n" ); document.write( "\"160%2B0.20x-32%3C140%2B0.25x-35\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"128%2B0.20x%3C105%2B0.25x\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "\"0.20x-0.25x%3C105-128\" Subtract 0.25x from both sides. Subtract 128 from both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"-0.05x%3C-23\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "\"x%3E460\" Divide both sides by -0.05. Remember that dividing both sides by a negative number will flip the inequality sign.\r
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\n" ); document.write( "\n" ); document.write( "So if she has any bills over $460, then Plan B will cost less than Plan A. \r
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\n" ); document.write( "\n" ); document.write( "If you're skeptical, try some values of 'x' that are around $460. Try x=400, x=450, x=500 (and maybe more) and you'll notice that plan B will become cheaper after you pass x=450.\r
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\n" ); document.write( "\n" ); document.write( "Note: the plans cost the same when the bill is $460. This is cross over point when the plans switch in cost.
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