. The team finished the race in a total of 190.729 seconds • First team member: 46.685 seconds • Second team member: 48.869 seconds • Third team member: 49.33 seconds How many seconds did it take the fourth team member to complete his part the race?
The Correct Answer and Explanation is:
Answer: 45.845 seconds
To work out the missing split time, start with the overall time recorded for the four-person relay: 190.729 s. This represents the combined duration of the four individual legs because in a relay the clock never stops; each athlete’s time contributes directly to the total.
The problem already supplies the first three individual splits:
• First athlete: 46.685 s
• Second athlete: 48.869 s
• Third athlete: 49.330 s
Add those three values to see how much of the total has already been accounted for.
46.685 s + 48.869 s = 95.554 s
95.554 s + 49.330 s = 144.884 s
So 144.884 s of the 190.729 s total is explained by the first three racers. The difference between the total and this subtotal must therefore be the fourth racer’s contribution.
190.729 s − 144.884 s = 45.845 s
That subtraction can be verified quickly on a calculator or by doing columnar subtraction with three decimal places (thousandths of a second). Aligning decimals ensures we keep the precision consistent:
190.729
− 144.884
= 45.845
Because each of the input times is given to the nearest thousandth of a second, it is appropriate to present the result to the same precision: 45.845 s. Rounding to fewer places would discard meaningful information, while quoting more places would imply accuracy the original data do not support.
Conceptually, this exercise demonstrates a common technique in time-splitting events: when some split times are missing, subtraction of known splits from the official aggregate reveals the unknown leg. Accurate bookkeeping of decimal places is essential, especially in elite sport where hundredths of a second can change medal positions.
Therefore, the fourth Korean wheelchair racer completed his quarter of the relay in 45.845 seconds, contributing the final piece that brought the team’s cumulative performance to 190.729 seconds, precisely.
