Given:
A biased 3-colored spinner was spun 240 times. It landed on Red n times, on Orange 3n times and on Yellow 8n times.
To find:
The expected number of times it land on Red if you spin this spinner 1000 times.
Solution:
A biased 3-colored spinner was spun 240 times. It landed on Red n times, on Orange 3n times and on Yellow 8n times. So,
[tex]n+3n+8n=240[/tex]
[tex]12n=240[/tex]
[tex]n=\dfrac{240}{12}[/tex]
[tex]n=20[/tex]
The value of n is 20. It means the spinner land on red 20 times if the spinner was spun 240 times. So, the probability of getting red is:
[tex]P(Red)=\dfrac{20}{240}[/tex]
[tex]P(Red)=\dfrac{1}{12}[/tex]
If you spin this spinner 1000 times, then the expected number of times to getting red is:
[tex]E(Red)=1000\times P(Red)[/tex]
[tex]E(Red)=1000\times \dfrac{1}{12}[/tex]
[tex]E(Red)=83.333...[/tex]
[tex]E(Red)\approx 83[/tex]
Therefore, the expected number of times to land on red is 83.