Find the probability of no failures in five trials of a binomial experiment in which the probability of success is [tex]30\%[/tex].

Round to the nearest tenth of a percent.

[tex]P = \, ? \, \%[/tex]

[tex]\square[/tex]



Answer :

To find the probability of no failures in five trials of a binomial experiment where the probability of success on a single trial is 30%, follow these steps:

1. Understand the Binomial Experiment Parameters:
- Number of trials, [tex]\( n \)[/tex]: 5
- Probability of success on each trial, [tex]\( p \)[/tex]: 30%, or 0.3

2. Define the Probability of Failure:
- The probability of failure on each trial, [tex]\( q \)[/tex], is given by [tex]\( 1 - p \)[/tex]:
[tex]\[ q = 1 - 0.3 = 0.7 \][/tex]

3. Identify the Number of Failures:
- We are looking for the probability of zero failures ([tex]\( k = 0 \)[/tex]) over the five trials.

4. Use the Binomial Probability Formula:
- The binomial probability formula is:
[tex]\[ P(X = k) = \binom{n}{k} p^k q^{n-k} \][/tex]
where [tex]\( \binom{n}{k} \)[/tex] is the binomial coefficient, calculated as:
[tex]\[ \binom{n}{k} = \frac{n!}{k!(n-k)!} \][/tex]

5. Plug in the Values:
- For [tex]\( k = 0 \)[/tex]:
[tex]\[ \binom{5}{0} = \frac{5!}{0!(5-0)!} = \frac{1}{1 \cdot 1} = 1 \][/tex]
- So, the probability of zero failures is:
[tex]\[ P(X = 0) = 1 \cdot (0.3)^0 \cdot (0.7)^5 \][/tex]
- Simplifying:
[tex]\[ P(X = 0) = 1 \cdot 1 \cdot 0.16807 = 0.16807 \][/tex]

6. Convert the Probability to a Percentage:
- Multiply by 100 to convert the decimal probability to a percentage:
[tex]\[ 0.16807 \times 100 = 16.807 \][/tex]
- Round to the nearest tenth of a percent:
[tex]\[ \text{Rounded Percentage} \approx 16.8\% \][/tex]

Therefore, the probability of no failures in five trials of this binomial experiment, rounded to the nearest tenth of a percent, is:

[tex]\[ P \approx 16.8\% \][/tex]