The spinner below shows

5
equally sized slices. Karen spun the dial
1000
times and got the following results.
OutcomeWhiteGreyBlackNumber of Spins
412
382
206
Fill in the table below. Round your answers to the nearest thousandth.
(a)From Karen's results, compute the experimental probability of landing on black.
(b)Assuming that the spinner is fair, compute the theoretical probability of landing on black.
(c)Assuming that the spinner is fair, choose the statement below that is true:
With a large number of spins, there must be no difference between the experimental and theoretical probabilities.
With a large number of spins, there might be a difference between the experimental and theoretical probabilities, but the difference should be small.
With a large number of spins, there must be a large difference between the experimental and theoretical probabilities.

1 answer

To analyze Karen's spinner results and compute the necessary probabilities, let's complete each part step-by-step.

(a) Experimental Probability of Landing on Black:

To find the experimental probability, we use the formula:

\[ P(\text{Black}) = \frac{\text{Number of Spins on Black}}{\text{Total Spins}}. \]

From the data provided:

  • Number of spins on Black = 206
  • Total spins = 1000

Now we calculate:

\[ P(\text{Black}) = \frac{206}{1000} = 0.206. \]

Rounding to the nearest thousandth, we get:

\[ P(\text{Black}) \approx 0.206. \]

(b) Theoretical Probability of Landing on Black:

Assuming the spinner is fair and has 5 equally sized slices (White, Grey, Black, and two other colors), the theoretical probability of landing on any specific color (including Black) is given by:

\[ P(\text{Black}) = \frac{1}{\text{Total number of slices}} = \frac{1}{5} = 0.2. \]

(c) True Statement Regarding Large Number of Spins:

The correct statement regarding the experimental vs. theoretical probabilities with a large number of spins is:

With a large number of spins, there might be a difference between the experimental and theoretical probabilities, but the difference should be small.

This acknowledges that while the experimental probability may vary due to random chance, over many trials, the experimental probability is expected to approximate the theoretical probability closely.

Summary of Results:

(a) Experimental Probability of landing on Black: 0.206
(b) Theoretical Probability of landing on Black: 0.2
(c) True Statement: With a large number of spins, there might be a difference between the experimental and theoretical probabilities, but the difference should be small.