I assume you mean 3.25 repeating as in the .25 repeating, not just the 5 or something like that. Anyways, here's the solution:
Let x = 3.25 repeating
100x = 325.25 repeating on the 0.25 (you can do this by just moving the decimal place back 2 times, and since repeating decimals go on forever, it's like you just added another "2" and "5" to the front right behind the 3. But it is still mathematically correct. Anyways, we subtract 1x from both sides, but on the right side of the equation, we actually substitute the value of x in, so it would be
100x-x on the left, and
325.25 repeating - 3.25 repeating on the right side.
On the left, 100x becomes
99x
and on the right side, the repeating decimals cancel out to give you
322 (subtracting the 3 still)
so we currently have
99x=322
divide both sides by 99 to get
x = 322/99
which cannot be simplified, so the final fraction is
[tex] \frac{322}{99} [/tex]
or
[tex]3 \frac{25}{99} [/tex]
