Answer:
Jack took 6 minutes and 33 seconds longer to complete the race.
Step-by-step explanation:
54 minutes minus 47 minutes would equal 7 minutes longer, but Jack was not as far into the minute when he completed it as Ben was when he completed it, so the difference in time is actually going to be a bit less than 7 minutes. So the difference is going to be 6 minutes and the number of seconds between 39 and 12, with 39 going past the minute, that is. That equals out to 33 seconds, so the total difference in time is 6 minutes and 33 seconds.