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When traveling between a and B, the speed from a to B is 45km / h, and the speed when returning from the original road is 60km / h, Based on the above information, please put forward a problem and use the equation to solve the problem
When traveling between a and B, the speed from a to B is 45km / h, and the speed when returning from the original road is 60km / h,
If the return time is 1 / 3 hour less than that of the past, calculate the distance between a and B
Suppose the distance between a and B is x km
Countable equation: X / 45 - X / 60 = 1 / 3,
The solution is: x = 60, that is: the distance between a and B is 60 km
After 10 minutes of starting from a certain place by bicycle at a speed of 5 m / s, a has set out from the same place by motorcycle to catch up with a, and finally overtakes a 15 km away from the starting point
It's the speed of motorcycle B
Set V, then 5 * 10 * 60 + 5 * 15000 / v = 15000
The solution is v = 6.25m/s
A runs at a speed of 5 km / h, and after 2 hours, B starts from the same place by bike and goes along the same road
A runs at a speed of 5km / h, and two hours later, B starts from the same place and runs along the same road to catch up with A. However, the two of them agree that B should catch up with a no earlier than 1h and no later than 1.25h?
Of course, who is the answer? Adopt who ;-)
Let B use t time to catch up with a, then a's journey in this period of time is: 5 * 2 + 5 * t;
Let B's speed be K km / h, then B's distance in this period is k * t;
When B overtakes a, there is: 5 * 2 + 5 * t = k * t, and the solution is t = 10 / (K-5);
And 1 ≤ t ≤ 1.25, i.e. 1 ≤ 10 / (K-5) ≤ 1.25
13≤k≤15 （km/h）
Someone runs 5 kilometers per hour. If it takes 8 minutes less than running per kilometer by bicycle, how many times faster can he ride a bicycle than running?
Three times
It takes 12 minutes to run a kilometer and 4 minutes to cycle
So it's 3
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