Yes and no.
if there’s 1,000 people in the town then 250 people would be subscribed to the newspaper. 20% of 250 is 50 and 80% of 50 is 40. obviously 40 is not 80% of 1,000 but 40 IS 80% of the people who voted.
with that information you should be able to draw the diagram. sorry i couldn’t help more i have school tomorrow so that’s all i could do. hope that helps though!