Today Puzzle #577
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Puzzle No. 577– Friday 27 September
The World Athletics Championships starts today. British sprinter Dina Asher-Smith is competing in the 100m, 200m and 4 x 100m relay. If she matches her 100m and 200m Personal Bests of 10.85 seconds and 21.89 seconds, what is the difference in average speeds in km/hour between the two?
Today’s #PuzzleForToday has been set by Bobby Seagull, a school Maths teacher and Cambridge University Doctorate student
Click here for the answer
Work out the average speed during 100m and 200m respectively using speed = distance / time. Ensure you convert both to the correct units of km and hours.
100m
Speed = [100m/1000m] / [10.85/60 x 60] = 33.18km/h
200m
Speed = [200m/1000m] / [21.89/60 x 60] = 32.89km/h
The 100m is 0.29 km/hr faster.
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