We were given that:
Each of 3 friends spin a coin 87 times
Total Trial for each friend = 87
Friend 1: Heads = 38, Tails = 49
Friend 2: Heads = 43, Tails = 44
Friend 3: Heads = 28, Tails = 59
The formula for the relative frequency of an event is given by:

We will proceed to solve for the cumulative frequency of getting "heads" as shown below:
Friend 1

Friend 2:

Friend 3:

We will obtain the