Question 178261
Ok.  Let's call the number you think of x.  Then if you halve it and subtract 1 from it, that is 
{{{(x/2)-1}}}
  If the result is double the amount obtained by dividing the number by 3 and subtracting 4 from it, that would be 
{{{2((x/3)-4)}}}
So, we have
{{{(x/2)-1=2((x/3)-4)}}}
Now, I am going to distribute through the 2 on the right hand side:
{{{(x/2)-1}}}=(2/3)x-8}}}
Now I am going to subtract x/2 from both sides:
{{{-1=(2/3)x-(1/2)x-8}}}
Now, add 8 to both sides:
{{{7=(2/3)x-(1/2)x}}}
Now, we need to find a common denominator for the right hand side, which is 6.  So I will transform each question:
{{{7=(4/6)x-(3/6)x}}}
{{{7=(1/6)x}}}
Lastly, we divide both sides by (1/6), which is the same as multiplying both sides by (6/1).  So,
{{{42=x}}}
Thus the number you thought of is 42.