Jackson jogged from point A to post B at a speed of 200 m/min and Gary jogged from point B to point A at a speed 10 m/min slower than Jackson's speed. Both of them started jogging at the same time and did not change their speeds throughout the journey. When Jackson reached point A, Gary was still 120 m away from Point B. What was the distance between point A and point B?
Teacher's comment
The speed difference caused the difference in the distance travelled by both boys.
+69 Jackson jogged from point A to point B at a speed of 200 m/min and Gary jogged from point B to point A at a speed 10 m/min slower than Jackson's speed. Both of them started jogging at the same time and did not change their speeds throughout the journey. When Jackson reached point A, Gary was still 120 m away from Point B. What was the distance between point A and point B?
Jackson's speed = 200 m/min
Gary's speed = 190 m/min
At the end of the first minute, Gary is 10 m behind Jackson. Every minute after the first, Gary falls behind a futher 10 m. So, 120/10 = 12 minutes must have passed for that much distance to be in between Gary and Jackson. That means Jackson has reached point B in 12 minutes, so we can do 12*200 to find the total distance between the points.
12*200 = 2400
2400 m/2.4 km between point A and B
