Final answer:
Gwendolyn is faster than Francine in the 100-meter dash, but the exact difference in their times cannot be determined without additional information.
Step-by-step explanation:
To determine how much faster Gwendolyn is than Francine in the 100-meter dash, we need to find the difference in their times. Gwendolyn can run the 100-meter dash in 3/4 seconds, which can be written as 0.75 seconds. Francine's best time is 18.65 seconds. To find the difference, we subtract Francine's time from Gwendolyn's time: 0.75 seconds - 18.65 seconds = -17.9 seconds.
Gwendolyn is faster than Francine by 17.9 seconds. However, it is important to note that negative time doesn't make sense in this context. We can conclude that Gwendolyn is faster than Francine, but we cannot specify the exact number of seconds without additional information.