probability

Question

An experiment consists of spinning the hand of the numbered disc as follows 1,2,3,4,5, observing the region in which the pointer stops - (a) what is an appropriate sample space for this experiment?  (b) describe the event "the spinner points to the #2".  (c)  describe the event "the spinner points to an odd #".

Answer 1

Assuming the regions on the disc are all the same size...

 

 

 

An appropriate sample space includes all possible outcomes:

 

{spinner stops on 1, spinner stops on 2, spinner stops on 3, spinner stops on 4, spinner stops on 5}

 

 

 

The event "the spinner points to the number 2" occurs when the "spinner stops on 2." That's one of the five possible outcomes in our sample space, so its probability is 1/5.

 

 

 

The event "the spinner points to an odd number" occurs when the "spinner stops on 1," "spinner stops on 3," or "spinner stops on 5." That's three of the five possible outcomes in our sample space, so its probability is 3/5.