Matthew manages the packaging department of his company. Yesterday, the department operated for only 4 hours due to a company pi
cnic, and they only completed 112 packages. Today, his department will complete 43 packages per hour. If Matthew wants the average rate of packing over the two days to be at least 39 packages per hour, then what is the minimum number of hours that the department must operate today to compensate for yesterday's company picnic?
