Question 339469
Let {{{f}}} = the number of $5 bills she had
Let {{{t}}} = the number of $10 bills she had
given:
{{{5f + 10t = 460}}}
{{{f >t}}}
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Note that there has to be an even number of $5 bills 
to get $460
What would {{{f}}} and {{{t}}} be if {{{f = t}}}
{{{5f + 10f = 460}}}
{{{15f = 460}}}
{{{f = 30.67}}}
This doesn't work, since {{{f}}} needs to be an integer
I'll try {{{f = t + 1}}}
{{{t = f - 1}}}
Substituting:
{{{5f + 10*(f - 1) = 460}}}
{{{5f + 10f - 10 = 460}}}
{{{15f = 470}}}
{{{f = 31.33}}} doesn't work
I'll try {{{f = t + 2}}}
{{{t = f - 2}}}
substituting:
{{{5f + 10*(f - 2) = 460}}}
{{{5f + 10f - 20 = 460}}}
{{{15f = 480}}}
{{{f = 32}}}
This looks like {{{32}}} isthe smallest number of $5's that
will give me $460 and still have more $5's than
$10's
check:
{{{5f + 10t = 460}}}
{{{5*32 + 10t = 460}}}
{{{10t = 460 - 160}}}
{{{10t = 300}}}
{{{t = 30}}}
The answer is (A)