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The maximum running speed of the Hound is 30m / s, and the running speed of the hare is 72km / h. how long does it take for the hound to capture a hare with the first 20m?
72km/h=20m/s
Hounds chase 30-20 meters in one second, so it takes 2 seconds to chase 20 meters
Hound found it 10 meters in front of a running hare, immediately catch up, hound step is big, it runs 5 steps, rabbit to run 9 steps (in ↓
But the rabbit moves fast, the hound runs 2 steps, but the rabbit runs 3 steps. How many meters can the hound run at least to catch up with the rabbit?
Let the rabbit step be n meters and the dog 9 / 5 * n
Let the rabbit run one step for a, then the dog's time is 3 / 2 * a;
Rabbit speed n / A
Dog's speed (9 / 5 * n) / (3 / 2 * a)
I want to catch up with Mimi
Rabbit running time = dog running time
The distance a rabbit runs divided by its speed = the distance a dog runs divided by its speed
m / ( n/a) = (m+10)/(9/5*n)/(3/2*a)
The solution is m = 10
The hound found a hare in front of it 15 meters away, and immediately caught up with it. The hound's pace was big, it ran 4 steps, the rabbit ran 9 steps, and there was still a lot of room below
But the rabbit moves fast, the hound runs 2 steps, but the rabbit can run 3 steps. At least how many meters does the hound have to run to catch up with the rabbit?
I was confused when I just read the question. The main reason is that the unit is relatively remote, so in the process, it is regarded as a rabbit run of 4 meters and a hound run of 9 meters
The hound can run 2 steps, but the rabbit can run 3 steps, which indicates the number of steps with the same time
So the speed of Hound is 9 × 2 = 18, rabbit is 4 × 3 = 12
Because catching up with the rabbit means that the time of two runs is equal, so let's set the time x equation
18x = 12x + 15 x = 2.5, so we have to run 2.5 × 18 + 15 = 60
It looks boring, but it's very simple. I'm just talking about it
In the forest, the hound found a rabbit running 20 meters in front of him, and immediately caught up with him. The hound had a big step. It ran 5 steps, and the rabbit had to run 9 steps, but the rabbit was fast. When the hound ran 2 steps, the rabbit could run 3 steps. How far could the hound run to catch up with the hare?
If the hound runs 2 × 5 = 10 steps and the rabbit runs 9 × 2 = 18 steps, the rabbit can only run 3 × 5 = 15 steps in the time of 2 × 5 = 10 steps; then the speed ratio of the hound to the rabbit is 18:15 = 6:5. Suppose the hound runs x meters and the hare runs x-20 meters. X: (x-20) = 6:5 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; &X = 120 A: The Hound runs 120 meters to catch up with the hare
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