Ai Tong School P6 SA1 2006 Math (Q44)

John and Ken took part in a race. When Ken had completed the race in 20 minutes, John had only run 3/5 of the distance. John’s average speed for the race was 60 m/min less than Ken’s.
(a) Find the distance of the race.
(b) What was John’s speed in m/min?

Solution



2 units ----- 60 m/min
1 unit ----- 60 m/min divided by 2 = 30 m/min
(John’s speed) 3 units ----- 30 m/min x 3 = 90 m/min

Ken’s speed ----- 90 m/min + 60 m/min = 150 m/min
Total distance ----- John’s speed x time
= 150 m/min x 20 min = 3000 m

Answers: (a) The total distance is 3000m. (b) John’s speed was 90 m/min.