Solution: Let the first half time be X and the second half time be X, in which the total time for him to complete 45% of the task is X+Y, and the time for him to complete all the later parts is X+X-(X+Y) = X-Y. The total equation is 8x+12Y+12 (X-Y) = 544. In the first 27 minutes, 8 yuan per minute, that is, 2 16 yuan; The second 27 minutes, per minute 12 pieces, that is, 324 pieces were processed when 45% of the workload was completed; In other words, 8 pieces per minute in the first 27 minutes, completing 2 16 pieces; In addition, the processing capacity of 12 pieces per minute is 243-263. In other words, it takes 27 minutes plus 2 minutes 15 seconds to complete 45% of the workload, that is, 29 minutes 15 seconds, so the estimated time is 8: 30.45 seconds. Add Q 2205985000 if you don't explain it in detail.