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The distance between a and B is 40km. A starts for 1.5h and then B starts. A is behind and B is in front. They walk in the same direction. The speed of a is 8km / h and that of B is 6km / h. how many hours after a start, can a catch up with B?
Let a catch up with B after starting for X hours. From the meaning of the question: 8x-6 (x-1.5) = 40, the solution is x = 15.5. Answer: a catch up with B after starting for 15.5 hours
The distance between a and B is 40km. A starts for 1.5h, B starts, a is behind, and B is in front. They both think the same way,
The speed of a is 8km / h, and that of B is 6km / h. After a few hours of departure, a will catch up with B
Speechless=/
Suppose B is overtaken by a after X hours of departure
1.5*8+8X-40=6X
12+8X-40=6X
2X=28
X=14
14+1.5=15.5
A overtakes B 15.5 hours after departure
Note: the question is that a will catch up with B a few hours after starting, so you should pay attention not to set it wrong
Xiaoming and Xiaoliang are 40km apart. Xiaoming starts for 1.5h and then starts. Xiaoming is in the back and Xiaoliang is in the front. They walk in the same direction. Xiaoming's speed is 8km / h and Xiaoliang's speed is 6km / h. how many hours after Xiaopeng starts, can he catch up with Xiaoliang?
Xiao Ming started for 1.5 hours and walked 8 × 1.5 = 12 (km)
This is the problem of catching up. Distance between the two places △ speed difference = catching up time
（40-12）÷（8-6）
=28÷2
=14 hours
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