Question

During Fitness Day at school, Destiny and her classmates took part in a pull-up competition, keeping track of the results. Number of pull-ups Number of people 8 2 18 1 40 2 54 2 60 1 93 2 X is the number of pull-ups that a randomly chosen person did. What is the expected value of X? Write your answer as a decimal.

Answer 1

46.8 pull-ups

Step-by-step explanation:

To calculate the expected value, we first will multiply each number of pull-ups by its respective number of people, so:

Pull-ups People Pull-ups x People

8 2 8 x 2 = 16

18 1 18 x 1 = 18

40 2 40 x 2 = 80

54 2 54 x 2 = 108

60 1 60 x 1 = 60

93 2 93 x 2 = 186

Now, we need to sum all the results:

16 + 18 + 80 + 108 + 60 + 186 = 468

Finally, to know the expected value, divide this number by the total number of people:

`(468)/(2+1+2+2+1+2)=(468)/(10)=46.8`

Therefore, the expected value is 46.8 pull-ups