Final answer:
The average time until a printer jams again is 12 days.
Step-by-step explanation:
To calculate the average time until a printer jams again, we need to find the mean average of the times between paper jams for each printer. Let's assume that the time until a printer jams again follows an exponential distribution. The mean of an exponential distribution is equal to 1 divided by the rate parameter. In this case, since each printer jams on average twelve times a day, the rate parameter for each printer is 1/12. Therefore, the average time until a printer jams again is 1/(1/12) = 12 days.