Whenever you see a set of percentages, always ask yourself, do they add up to 100%, and should they? In the first example, the numbers in the pie chart are not percentages because they add up to 80, not to 100%.
To convert them to real percentages, we must multiply them by 100%/80. Why? Because in this example, 80 means "everything" so that should map to 100%. To get there you first divide by the maximum (80), then multiply by 100%.
So the blue car slice with 20, maps to 20*100/80 = 25.
The second question is totally different. Here, every equal sized slice represents some score. The probability of each slice is 100/5 = 20%. there are 3 slices with a number greater than 5, so the probability is 3x20=60%, I would say the probability is likely, since it is larger than 50%.