Question 1206513
<pre>
COIN          HOW MANY        VALUE

 50c            2x            0.50*2x

 20c             x            0.20x

 10c            5*2x=10x     0.10*10x

SUM                          $15.40
</pre>


the sum of the values, first summarized,
{{{x+0.2x+x=15.4}}}

-

{{{2.2x=15.4}}}

{{{highlight(x=7)}}}--------------of the 20 c coins.

This means  {{{highlight(highlight(14))}}} of the 50 c coins.