Question 14194
well, you seem to have mentioned a concept called cross multiplication.  That is exactly what you want to use.  Basically, you have the idea, but it was very hard to understand even for me. 
You can set up the problem as 
{{{9/8 = x/6}}}
Then you cross multiply so the following equation is formed:
{{{9*6=8*x}}}
{{{9*6=54}}}
So you can get the following equation.
{{{54=8x}}}
In order to get the value of X, you need to get rid of the 8, so you divide both sides by 8. 
{{{54/8=x}}}
Then you can just simplify to get the final answer.
{{{54/8 = 27/4}}}
That fractions ends up to be an improper fraction and you can always convert it to a mixed number of 6 3/4.  
while you answer is correct, your explanation was a bit confusing
Hope this helps your daughter out!