The probability that a randomly selected 2 2​-year-old male garter snake garter snake will live to be 3 3 years old is 0.98861 0.98861. ​(a) What is the probability that two randomly selected 2 2​-year-old male garter snake garter snakes will live to be 3 3 years​ old? ​(b) What is the probability that seven seven randomly selected 2 2​-year-old male garter snake garter snakes will live to be 3 3 years​ old? ​(c) What is the probability that at least one of seven seven randomly selected 2 2​-year-old male garter snake garter snakes will not live to be 3 3 years​ old? Would it be unusual if at least one of seven seven randomly selected 2 2​-year-old male garter snake garter snakes did not live to be 3 3 years​ old?

Respuesta :

Answer:

a. [tex]Probability = 0.97735[/tex]

b. [tex]Probability = 0.92294[/tex]

c. [tex]P(At\ Least\ One) = 1[/tex]

No, it is not unusual if at least 1 lives up to 3.

Step-by-step explanation:

Given

Represent the probability that a 2 year old snake will live to 3 with P(Live);

[tex]P(Live) = 0.98861[/tex]

Solving (a): Probability that two selected will live to 3 years.

Both snakes have a chance of 0.98861 to live up to 3 years.

So, the required probability is:

[tex]Probability = P(Live)\ and\ P(Live)[/tex]

[tex]Probability = 0.98861 * 0.98861[/tex]

[tex]Probability = 0.9773497321[/tex]

[tex]Probability = 0.97735[/tex] --- Approximated

Solving (b): Probability that seven selected will live to 3 years.

All 7 snakes have a chance of 0.98861 to live up to 3 years.

So, the required probability is:

[tex]Probability = P(Live)^n[/tex]

Where [tex]n = 7[/tex]

[tex]Probability = 0.98861^7[/tex]

[tex]Probability = 0.92294324145[/tex]

[tex]Probability = 0.92294[/tex] --- Approximated

Solving (c): Probability that at least one of seven selected will not live to 3 years.

In probabilities, the following relationship exist:

[tex]P(At\ Least\ One) = 1 - P(None).[/tex]

So, first we need to calculate the probability that none of the 7 lived up to 3.

If the probability that one lived up to 3 years is 0.98861, then the probability than one do not live up to 3 years is 1 - 0.98861

This gives:

[tex]P(Not\ Live) = 0.01139[/tex]

The probability that none of the 7 lives up to 3 is:

[tex]P(None) = P(Not\ Live)^7[/tex]

[tex]P(None) = 0.01139^7[/tex]

Substitute this value for P(None) in

[tex]P(At\ Least\ One) = 1 - P(None).[/tex]

[tex]P(At\ Least\ One) = 1 - 0.01139^7[/tex]

[tex]P(At\ Least\ One) = 0.99999999999997513055642436060443621[/tex]

[tex]P(At\ Least\ One) = 1[/tex] ---- Approximated

No, it is not unusual if at least 1 lives up to 3.

This is so because the above results, which is 1 shows that it is very likely for at least one of the seven to live up to 3 years