A. Volley Ball game: 0.20
B. Rugby 7s game: 90%
A. Volley Ball game: 12 ≤ x < 21
To calculate the probability, the first step is to evaluate the number of people meeting the requirement and then the number of the total population.
In this case, let's first sum up the total population, meaning the total audience at the Volley Ball game. If we sum up all attendance numbers for the Volley Ball game (first column), we get 700 + 1,000 + 3,050 + 250 = 5,000 people.
Now, let's find out how many people we have in that attendance being 12 or older but less than 21. That's the second line of the table, so 1,000.
That means that the probability the Fan Cam gets one of those 12 ≤ x < 21 fans is 1,000 / 5,000, so 1/5, which is equal to 20% or 0.20
B. Rugby 7s game: x > 12
As before, to calculate the probability, the first step is to evaluate the number of people meeting the requirement and then the number of the total population.
The total population is the total attendance of the game, so 500 + 1,000 + 2,500 + 1,000 = 5,000 people in the stadium.
How many of them are NOT less than 12 years of age? We have to sum up the last 3 rows of the table: 1,000 + 2,500 + 1,000 = 4,500 people 12 or older.
So, what's the possibility one of those 12 or older will be spotted by the Fans Cam? 4500 out of 5,000 = 9/10, or 90%.