<PRE><B>Question 550502</B>
A:  G pays 90 + .3(x-90)
B:  G pays 100 + .2x
In each case X is the total bill.  In A, she pays 30% of the remainder of the bill which is x-90.  In B, she pays 20% of the bill in addition to the $100.&lt;P&gt;
Find when B is cheaper by finding when B is &lt; A.&lt;P&gt;
90 + .3(x-90) &gt; 100 + .2x&lt;P&gt;
90+.3x-27 &gt; 100 + .2x&lt;P&gt;
.1x &gt; 37&lt;P&gt;
x &gt; 370

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