Question

mr. fowler, a track coach, recorded the number of runners on all the nearby track teams. number of runners 39 39 39 74 74 74 74 74 83 83. find the number of members that a randomly chosen team has. what is the expected value of x? write your answer as a decimal.

Explanation:

Step1: Calculate total number of teams

There are 3 teams with 39 members, 5 teams with 74 members and 2 teams with 83 members. So the total number of teams is $3 + 5+2=10$.

Step2: Calculate the sum of products of number of members and their frequencies

The sum is $39\times3 + 74\times5+83\times2=117 + 370+166 = 653$.

Step3: Calculate the expected value

The expected value is the sum divided by the total number of teams. So it is $\frac{653}{10}=65.3$.

Answer:

$65.3$