Answer:
0.5667
Step-by-step explanation:
If there are 30 people in total and 7 of them didn't visit any of the places, we have 23 people that visit the Eiffel tower or the Notre-dame cathedral because
30 - 7 = 23
Now, we know that 13 people visited the Eiffel tower and 16 people visited the Notre-dame cathedral. If we add these numbers, we get
13 + 16 = 29
Since 29 is greater than 23 and 29 - 23 = 6, we get that 6 people visited the Eiffel tower and the Notre-dame cathedral.
Then,
13 - 6 = 7
16 - 6 = 10
So, 7 people only visited the Eiffle tower and 10 people only visited the Notre-dame cathedral. It means that 17 people (10 + 7 = 17) from the 30 visited only 1 of the 2 places.
Then, the probability is calculated as
Therefore, the answer is 0.5667