The pressroom supervisor for a daily newspaper is being pressured to find ways to print the paper closer to distribution time, thus giving the editorial staff more leeway for last-minute changes. She has the option of running the presses at “normal” speed or at 110 percent of normal—“fast” speed. She estimates that they will run at the higher speed 60 percent of the time. The roll of paper (the newsprint “web”) is twice as likely to tear at the higher speed, which would mean temporarily stopping the presses,
- If the web on a randomly selected printing run has a probability of 0.112 of tearing, what is the probability that the web will not tear at normal speed?
- If the probability of tearing on fast speed is 0.20, what is the probability that a randomly selected torn web occurred on normal speed?
Solution
