Question: ASSEMBLY-TIME STUDIES A time study was conducted by the production manager of Universal Instruments to determine how much time it took an assembly worker to complete a certain task during the assembly of its Galaxy home computers. Results of the study indicated that 20% of the workers were able to complete the task in less than 3 min, 60% of the workers were able to complete the task in 4 min or less, and 10% of the workers required more than 5 min to complete the task. If an assembly-line worker is selected at random from this group, what is the probability that
a. He or she will be able to complete the task in 5 min or less?
b. He or she will not be able to complete the task within 4 min?
c. The time taken for the worker to complete the task will be between 3 and 4 min (inclusive)?