In: Statistics and Probability
particular lake is known to be one of the best places to catch a certain type of fish. In this table, x = number of fish caught in a 6-hour period. The percentage data are the percentages of fishermen who caught x fish in a 6-hour period while fishing from shore. x 0 1 2 3 4 or more % 43% 35% 15% 6% 1%
(b) Find the probability that a fisherman selected at random fishing from shore catches one or more fish in a 6-hour period. (Enter a number. Round your answer to two decimal places.)
(c) Find the probability that a fisherman selected at random fishing from shore catches two or more fish in a 6-hour period. (Enter a number. Round your answer to two decimal places.)
(d) Compute μ, the expected value of the number of fish caught per fisherman in a 6-hour period (round 4 or more to 4). (Enter a number. Round your answer to two decimal places.) μ = fish
(e) Compute σ, the standard deviation of the number of fish caught per fisherman in a 6-hour period (round 4 or more to 4). (Enter a number. Round your answer to three decimal places.) σ = fish
Solution :
| x | P(x) | x * P(x) | x2 * P(x) | 
| 0 | 0.43 | 0 | 0 | 
| 1 | 0.35 | 0.35 | 0.35 | 
| 2 | 0.15 | 0.3 | 0.6 | 
| 3 | 0.06 | 0.18 | 0.54 | 
| 4 | 0.01 | 0.04 | 0.16 | 
| Sum | 1 | 0.87 | 1.65 | 
(b)
The probability that a fisherman selected at random fishing from shore catches one or more
fish in a 6-hour period is,
= P(x 
 1)
= 0.35 + 0.15 + 0.06 + 0.01
= 0.57
(c)
The probability that a fisherman selected at random fishing from shore catches two or
more fish in a 6-hour period is ,
= P(x 
 2)
= 0.15 + 0.06 + 0.01
= 0.22
(d)
Mean = 
 = 
X * P(X) = 0.87 fish
(e)
Standard deviation = 
=
X
2 * P(X) - 
2
=  
1.65
- 0.872
= 0.945 fish