Math Problem Monday - July 13th, 2020 | Mathnasium Livermore, CA

Jul 13, 2020 | Livermore

Lower Elementary:
Question: Jimmy is training to run the mile for the Olympics. Last month his best time was 5 minutes and 7 seconds. This month he ran the mile 15 seconds faster. How fast did he run the mile this month?
Answer: 4 minutes and 52 seconds
Solution: This month Jimmy ran 15 seconds faster than 5 minutes and 7 seconds. To find how fast his time is we subtract 15 seconds from 5 minutes and 7 seconds.
15 can be broken into 7 and 8. By first subtracting 7 seconds from 5 minutes and 7 seconds, we get 5 minutes. 8 seconds faster than 5 minutes is 4 minutes and 52 seconds.

Upper Elementary: 
Question: Kristain, David, Andrew, and Ed are running the 4×100 relay race. If Kristain ran his leg of the race in 11.231 seconds, David in 11.4 seconds, Andrew in 11.019 seconds, and Ed in 10.85 seconds, what was the team’s final time?
Answer: 44.5 seconds
Solution: To find the answer to this question we add the times of all the team members together. This is done by lining up decimal so you are adding the correct place values.
        11.231
        11.4
        11.019
  +    10.85   
        44.5 seconds

Middle School: 
Question: In the 2008 Summer Olympics, China won 15 more gold medals, 17 fewer silver medals, and 8 fewer bronze medals than the United States. If China won 100 medals, how many medals did the United States win?
Answer: 110 metals
Solution: Start by finding the difference in medals earned by China and the United States.
        15 – 17 – 8 = –10
So, China won 10 fewer medals than the United States. If China won 100 metals then the United States won 110 metals.

Algebra and Up:
Question: Jamaica’s Usain Bolt holds the world record for the fastest 100m dash. At 9.58 seconds, what was his average speed in miles per hour? Let 1 meter equal 3.28 feet. Round your answer to the nearest hundredth.
Answer: 23.35 mph
Solution: To solve this problem, we first need to convert 100m to feet.
        1 meter = 3.28 feet
        So, 100 meters = 328 feet
Next we find how fast Usain Bolt ran in feet per second.
        328 feet ÷ 9.58 second ≈ 34.24 feet per second
Finally, we convert 34.24 feet per second to miles per hour.