Answer:
00:13 mm:ss
Step-by-step explanation:
There are 60 seconds in a minute. This fact can be used to convert the time period(s) to minutes and seconds either before or after you do the subtraction.
<h3>Difference</h3>
It is often convenient to do arithmetic with all of the numbers having the same units. Here, we are given two values in seconds and asked for their difference.
100 s - 87 s = (100 -87) s = 13 s
The difference between the two time periods is 0 minutes and 13 seconds.
<h3>Conversion</h3>
If you like, the numbers can be converted to minutes and seconds before the subtraction. Since there are 60 seconds in a minute, the number of minutes is found by dividing seconds by 60. The remainder is the number of seconds that will be added to the time in minutes:
87 seconds = ⌊87/60⌋ minutes + (87 mod 60) seconds
= 1 minute 27 seconds
100 seconds = ⌊100/60⌋ minutes + (100 mod 60) seconds
= 1 minute 40 seconds
Then the difference is found in the same way we would find a difference involving different variables. (A unit can be treated as though it were a variable.)
(1 min 40 s) -(1 min 27 s) = (1 -1 min) + (40-27 s) = 0 min 13 s
The difference between the two time periods is 0 minutes and 13 seconds.
