Answer: The required quantity of the extra fabric that will be left after making the skirt is 1.5 yards.
Step-by-step explanation: Given that Kate has
yards of fabric and needs
yards to make a skirt.
We are to find the quantity of the extra fabric that will be left after making the skirt.
According to the given information, we have

and

Therefore, the quantity of the extra fabric that will be left after making the skirt is given by

Thus, the required quantity of the extra fabric that will be left after making the skirt is 1.5 yards.