For a certain river, suppose the drought length Y is the number of consecutive time intervals in which the water supply remains below a critical value y0 (a deficit), preceded by and followed by periods in which the supply exceeds this critical value (a surplus). An article proposes a geometric distribution with p = 0.395 for this random variable. (Round your answers to three decimal places.)

(b) What is the probability that the length of a drought exceeds its mean value by at least one standard deviation?

Question

For a certain river, suppose the drought length Y is the number of consecutive time intervals in which the water supply remains below a critical value y0 (a deficit), preceded by and followed by periods in which the supply exceeds this critical value (a surplus). An article proposes a geometric distribution with p = 0.395 for this random variable. (Round your answers to three decimal places.)

(b) What is the probability that the length of a drought exceeds its mean value by at least one standard deviation?

anonymous · Answer

a) What is the probability that a drought lasts exactly 3 intervals? (Supply exceeds the critical level during the 4th time interval.) At most 3 intervals?
exactly 3 intervals    	 
.087
 
Correct: Your answer is correct.
at most 3 intervals    	 
.866
 
Correct: Your answer is correct.

anonymous · Answer

Needing help with part B.