Take a spin An online spinner has two colored regions_blue and yellow. According to the website, the probability that the spinner lands in the blue region on any spin is 0.80. Assume for now that this claim is correct. Suppose we spin the spinner 12 times and let X=the number of times it lands in the blue region.

a. Explain why Xis a binomial random variable.

b. Find the probability that exactly 8 spins land in the blue region.

Short Answer

Expert verified

(a) In this case, all of the binomial criteria are met. As a result, it's possible to say that X has a binomial distribution.

(b) The resultant probability is 0.1329

Step by step solution

01

Part (a) Step 1: Given Information

The total number of trials(n)=12

The likelihood of success (p)=0.80

02

Part (a) Step 2: Simplification

The random variable satisfies the following requirements X.

1. The probability of success (p) is equal to the probability that the spinner will land in the blue region.0.80is fixed.

2. The number of times the spinner spins is set.

3. Spins are unrelated to one another.

4. There are two possible outcomes: either the spinner lands in the blue region or it does not.

Here, all of the binomial criteria are met.

As a result, the binomial distribution X can be said to be followed.

03

Part (b) Step 1: Given Information

The total number of trials(n)is12

The likelihood of success(p)is0.80

04

Part (b) Step 2: Simplification

The likelihood of 8 spins landing in the blue region can be estimated as follows:

P(X=8)=C812×(0.80)8×(1-0.80)12-8

=0.1329

As a result, the necessary probability is0.1329.

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