A spinner has equal regions numbered 1 through 21. What is the probability that the spinner will stop on an even number or a multiple of 3?

Respuesta :

Answer:

[tex]\frac{2}{3}[/tex].        

Step-by-step explanation:        

We are told that a spinner has equal regions numbered 1 through 21.  

We can see that our both events are not mutually exclusive events, so will use formula [tex]P(A\cup B)=P(A)+P(B)-P(A\cap B)[/tex] to find our desired probability.

[tex]P(A\cup B)[/tex] = Probability of event A or event B.

[tex]P(A)[/tex] = Probability of event A.

[tex]P(B)[/tex] = Probability of event B.

[tex]P(A\cap B)[/tex] = Probability of event A and event B.      

Let us find probability that spinner will stop on an even number. Even numbers on spinner's region are: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20.  

[tex]P(\text{ Spinner will stop on an even number})=\frac{10}{21}[/tex]

Now let us find probability that spinner will stop on a multiple of 3. Multiples of 3 on the spinner's region are: 3,6,9,12,15,18,21.

[tex]P(\text{ Spinner will stop on a multiple of 3})=\frac{7}{21}[/tex]

Now we have to figure out probability that spinner will stop on an even number and multiple of 3. Both events happening at one time are: 6,12,18.

[tex]P(\text{Spinner will stop on an even number and multiple of 3})=\frac{3}{21}[/tex]

Now let us substitute our values in above mentioned formula.      

[tex]P(\text{Spinner will stop on an even number or multiple of 3})=\frac{10}{21}+\frac{7}{21}-\frac{3}{21}[/tex]

[tex]P(\text{Spinner will stop on an even number or multiple of 3})=\frac{17}{21}-\frac{3}{21}[/tex]

[tex]P(\text{Spinner will stop on an even number or multiple of 3})=\frac{14}{21}=\frac{2}{3}[/tex]

Therefore, probability that the spinner will stop on an even number or a multiple of 3 is [tex]\frac{2}{3}[/tex].    

   


Using it's concept, it is found that there is a 0.6667 = 66.67% probability that the spinner will stop on an even number or a multiple of 3.

What is a probability?

A probability is given by the number of desired outcomes divided by the number of total outcomes.

In this problem, there are 21 possible outcomes for the spinner.

  • 10 of those are even numbers.
  • 4 of those are odd numbers which are multiples of 3.

Hence:

[tex]p = \frac{14}{21} = \frac{2}{3} = 0.6667[/tex]

0.6667 = 66.67% probability that the spinner will stop on an even number or a multiple of 3.

More can be learned about the probability concept at https://brainly.com/question/15536019

ACCESS MORE
ACCESS MORE
ACCESS MORE
ACCESS MORE