When estimating, you want to round the dividend and the divisor to the nearest time table number (i.e. 5700 --> 5400). Finding the quotient is easier when you estimate. Writing the remainder as a fraction is simple. First, get your remainder and your divisor, then make it to a fraction.
ex:
If you get a remainder of 3, and have a divisor if 12, your remainder would be 3/12, or 1/4.