Over time, the number of original basic words in a language tends to decrease as words become obsolete or are replaced with new words. for a certain language proportion of words that remain after t millennia is a random variable that is exponentially distributed with a = 0.247. complete parts (a) and (b)
a. find the life expectancy and standard deviation of a word from this language.
what is the life expectancy?
4.05 millennia
what is the standard deviation?
4.05 millennia
b. what is the probability that a randomly chosen word from this language will remain after 2000 years?
(round to four decimal places as needed)