In: Statistics and Probability
Shortly before midnight, on April 14, 1912, the Titanic collided with an iceberg and sank.
Out of the 2249 passengers, 1514 died that night. The passengers’ summarized data are shown below:
1st Class | 2nd Class | 3rd Class | Crew | Total | |
Survived | 209 | 125 | 183 | 218 | 735 |
Died | 127 | 174 | 536 | 677 | 1514 |
336 | 299 | 719 | 895 | 2249 |
(Round all answers to four decimals)
Suppose a passenger is selected at random:
a) What is the probability that the passenger survived?
b) What is the probability that the passenger was in 3rd class?
c) What is the probability that the passenger survived and was a crew member?
d) What is the probability that the passenger was not in 1st class?
e) “Surviving” is (Click to select) dependent disjoint independent mutually exclusive of “being in 1st class”.
f) Suppose the passenger selected was in 2nd class. What is the probability that the passenger died?
g) What is the probability that a surviving passenger was a crew member?
h) What is the probability that the passenger survived or was a crew member?
i) “Surviving” and “being in 3rd class” are
Out of the 2249 passengers, 1514 died that night. The passengers’ summarized data are shown below:
1st Class | 2nd Class | 3rd Class | Crew | Total | |
Survived | 209 | 125 | 183 | 218 | 735 |
Died | 127 | 174 | 536 | 677 | 1514 |
336 | 299 | 719 | 895 | 2249 |
a) What is the probability that the passenger survived?
Total passengers=2249
Total passengers survived = 735
Probability that the passenger survived = 735 / 2249 = 0.3268119
Thus required probability = 0.3268
b) What is the probability that the passenger was in 3rd class?
Total passengers in 3rd class = 719
Total passengers =2249
Probability that the passenger was in 3rd class = passengers in 3rd class / Total passengers
= 719 /2249 = 0.3196976
Thus required probability = 0.3197
c) What is the probability that the passenger survived and was a crew member?
Crew member survived = 218
Total passengers=2249
Total passengers survived = 735
Probability that the crew member survived = Crew member survived/Total passengers
= 218 / 2249 = 0.09693197
Thus Probability that the crew member survived from all passengers on boat = 0.0969
Probability that the crew member survived = Crew member survived/Total passengers survived
= 218 / 735 = 0.2965986
Probability of survived crew member in all survived passengers = 0.2966
d) What is the probability that the passenger was not in 1st class?
Passenger in 1st class = 336
Total passengers=2249
Passenger was not in 1st class = Total passengers - Passenger in 1st class = 2249 - 336
= 1913
Probability that the passenger was not in 1st class = Passenger not in 1st class/ Total passengers
= 1913 / 2249 = 0.8506003
Thus required probability = 0.8506