Question 1182897
<pre>
Stephanie      40-4=36
Daughter         d
Sister          40
</pre>

Stephanie is "three times older than" d.
36 is "three times older than" d.


1 time older, is +d.
2 times older, is  +2d.
3 times older,    {{{36=d+3d}}}
{{{36=4d}}}
{{{highlight(d=9)}}}