On a straight road, Xiao Fang and Xiao Ming set out at the same time at a and B, 900 meters apart. Xiao Gang is 200 meters per minute and Xiao Ming is 250 meters per minute, Ask how much time after the two distance 2700 meters

On a straight road, Xiao Fang and Xiao Ming set out at the same time at a and B, 900 meters apart. Xiao Gang is 200 meters per minute and Xiao Ming is 250 meters per minute, Ask how much time after the two distance 2700 meters

Time = (2700-900) △ 250 + 200) = 1800 △ 450 = 4 minutes;
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A and B ride from the East and west at the same time, and meet each other in 8 hours. If a travels less than 1 kilometer per hour, B travels more than 3 kilometers per hour, it will take 7 hours
How many kilometers is the distance between the East and the west

Speed and phase difference = 1 + 1 = 2km
Distance = 2 ÷ (1 / 7-1 / 8) = 112 km

A and B are going east and west by bike at the same time. After 8 hours, they can meet each other. If a travels less than 1 kilometer per hour and B travels more than 3 kilometers per hour, they can meet each other after 7 hours. How many kilometers is the distance between the East and the West?

The original speed sum of the two is:
[(3-1)x7]÷(8-7)
=14÷1
=14 (km / h)
Distance between the two places:
14x8 = 112 (km)

A and B can meet each other in 8 hours by cycling from East and west at the same time. If a travels less than 1 kilometer per hour, B travels more than 3 thousand per hour
How many kilometers is the distance between the two places

8（x+y)=7(x-1+y+3)
8（x+y)=7(x+y)+14
（x+y)=14
8（x+y)=112
The distance between the two places is 112 km