Gabby does not have any fabric left, as she used more fabric than she had to start with.
How much fabric does Gabby have left after using 3215 yards, and what is the estimate?
Based on the information given, Gabby started with 578 yards of fabric and used 3215 yards of fabric. To estimate the amount of fabric Gabby has left, we need to subtract the amount of fabric used from the starting amount of fabric:
578 yards - 3215 yards = -2637 yards
Since the result is a negative number, it doesn't make sense in this context. It's possible that there was a mistake in the numbers given, or Gabby used more fabric than she had to start with.
Without further information or clarification, we cannot estimate the amount of fabric Gabby has left.