The problem presents a simple scenario involving a race between Vivian and her brother. We are given Vivian's finish time (63.9 seconds) and the time difference between her brother's finish and hers (8.58 seconds). Our goal is to determine the total time it took Vivian's brother to complete the race....
Solving the Problem
To find the brother's finish time, we simply need to add the time difference to Vivian's finish time:
Brother's finish time = Vivian's finish time + Time difference
Brother's finish time = 63.9 seconds + 8.58 seconds
Brother's finish time = 72.48 seconds
Answer
Therefore, it took Vivian's brother **72.48 seconds** to run the race.
Key Concepts
This problem involves a basic arithmetic operation - addition. We are essentially adding two quantities, time, to get a third quantity, also time. This is a common scenario in everyday life where we need to calculate elapsed time or time intervals.
Practice Problems
Here are some practice problems to reinforce the concept:
1. Sarah finished a marathon in 3 hours and 15 minutes. John finished 20 minutes later. How long did it take John to finish the marathon?
2. A train departs at 10:00 AM and arrives at its destination at 12:30 PM. Another train leaves the same station at 10:45 AM and arrives at the same destination at 1:15 PM. Which train took longer to reach its destination?
3. A movie starts at 7:00 PM and ends at 9:30 PM. A second movie starts at 7:45 PM and ends at 10:00 PM. Which movie is longer?
By practicing these problems, you can solidify your understanding of time calculations.