9614 1404 393
Answer:
add up the gaps and divide by their number
Explanation:
You find the average gap time the same way you find any average: divide the total of the gap times by the number of them.
The four gaps total 4 minutes 37 seconds, or 277 seconds. Their average is ...
(277 s)/4 = 69.25 s
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Each gap is computed by subtracting the first cyclist's time from each of the others.
In a spreadsheet such as this one, time computation can be done fairly easily. For the final conversion to seconds, we have to account for the fact that the spreadsheet stores time internally as a number of days. The 0:04:37 is converted to 277 seconds by multiplying it by 86400, the number of seconds in a day.