At Denver International Airport, 82% of recent flights have arrived on time. A sample of 13 flights is studied. Round the probabilities to at least four decimal places.

Find the probability that all 13 of the flights were on time. The probability that all 13 of the flights were on time is ___

Respuesta :

Answer:

P(X=13) = 0.0758

Step-by-step explanation:

Binomial Distribution Condition:

  1. There is only 2 outcomes → either arrive on time or not on time.
  2. There is a fixed number of trials → 13 flights.
  3. Each trial is independent of all other trials → assuming each flight does not affect others on their arrival time.
  4. The probability of success is constant → assuming success rate of 82% is constant for each trial.

Binomial Distribution Formula:

[tex]\boxed{P(X=x)=_nC_x\cdot p^x\cdot q^{n-x}}[/tex]

where:

  • P(X=x) = the probability of event X which has x successes
  • n = number of trial
  • x = number of successes
  • p = success rate
  • q = fail rate

Given:

  • X = event of flight arrives on time
  • n = 13
  • x = 13
  • p = 82% = 0.82
  • q = 1 - p = 1 - 0.82 = 0.18

[tex]P(X=13)=_{13}C_{13}(0.82)^{13}(0.18)^{13-13}[/tex]

                 [tex]\displaystyle=\frac{13!}{13!0!} (0.82)^{13}(0.18)^0[/tex]

                 [tex]=1\times(0.82)^{13}\times1[/tex]

                 [tex]=0.0758[/tex]