You were close.  The correct answer is - 1/4.  Whether you're dividing or multiplying, if there is one negative number and one positive number, the answer will always be negative.  And when dividing fractions, be sure to flip the second number then multiply.  In this case, the 3 turns into a 1/3.

I recommend reading Volume 2 of the Learn Math Fast System.  You already know must of the material in that book, so you can probably finish it in a week or two and be ready for prealgebra.  Use coupon code PT2026 to get 10% off your order.