You have 6 books on your shelf. you notice that 3 of them have red covers, and 3 of them have blue covers.
if you choose 2 books from your shelf at random, what is the probability that 1 will have a red cover and 1 will have a blue cover?
enter your answer as a fraction in simplest form, using the / symbol, like this: 42/53

The weibull distribution is widely used in statistical problems relating to aging of solid insulating materials subjected to aging and stress. use this distribution as a model for time (in hours) to failure of solid insulating specimens subjected to ac voltage. the values of the parameters depend on the voltage and temperature; suppose α = 2.5 and β = 190. (a) what is the probability that a specimen's lifetime is at most 250? less than 250? more than 300? (round your answers to four decimal places.) at most 250 less than 250 more than 300 (b) what is the probability that a specimen's lifetime is between 100 and 250? (round your answer to four decimal places.) (c) what value is such that exactly 50% of all specimens have lifetimes exceeding that value? (round your answer to three decimal places.) hr