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The hound catches up with the hare 30 meters ahead. The hound has a big step. It runs 4 steps. The hare runs 7 steps, but the hare moves fast. The hound runs 3 steps faster than the hare Please answer if you know
Your question should be: The Hound catches up with the hare 30 meters in front. The hound has a big step. It runs 4 steps. The hare has to run 7 steps. The rabbit is fast. The hound can run 4 steps when it runs 3 steps. How far can the hound run to catch up with the hare?
The first method is the number method
Suppose that dog's 4-step distance = rabbit's 7-step distance = 28 meters
Dogs run 7 meters per step, rabbits run 4 meters per step
Dog 3 step time = Rabbit 4 step time = 12 seconds
Dogs run 3 / 12 = 1 / 4 steps per second, rabbits run 4 / 12 = 1 / 3 steps per second
Dog runs per second: (1 / 4) × 7 = 7 / 4m
Rabbits run: (1 / 3) × 4 = 4 / 3M per second
According to the solution of the pursuit problem, the pursuit time is 30 ÷ (7 / 4-4 / 3) = 72 seconds
So: 7 / 4 × 72 = 126m
Analysis 2: drawing using speed ratio method
According to "the distance of a dog running 4 steps is equal to that of a rabbit running 7 steps"
According to "the time for dog to run 3 steps is equal to that for rabbit to run 4 steps", the speed ratio of dog to rabbit is 0
（3/4）：（4/7）= 21/16
According to the pursuit problem, the pursuit time can be calculated: 30 ÷ (21-16) = 6
So: 21 × 6 = 126 meters
When a hare runs 80 steps, the hound can catch up with it. When the hare runs 8 steps, the hound only needs 3 steps. When the hound runs 4 steps, the rabbit can run 9 steps. How many steps does the hound have to run to catch up with the hare?
If the time of hare running 9 steps and hound running 4 steps is 1 second, the distance of hare running 8 steps and hound running 3 steps is 8 × 4 = 32 (m), the speed of rabbit is 9 × 3 = 27 (m), the distance is 80 × 3 = 240 (m), and the catching up time is 240 (32 -...)
A hound found a hare running 50 meters away, and immediately jumped on it. If the speed of the Hound is three times that of the hare, how many meters can the hound run
50 + 50 / 2 = 75m
The hound found a rabbit running 10 meters in front of him, and immediately chased him. The hound's step was big. He ran two steps, but the rabbit had to run three
The action of the rabbit is fast. The hound can run 4 steps in 3 steps. How many meters does the hound have to run to catch up with the hare?
Suppose that the distance of the hound's step is a meter, and it can catch up with the time of the hare's step B, then the time of the hare's step B is 2 / 3 * a, and the time of the hare's step B is 4 / 3 * B, then the following formula appears:
A * b = 2 / 3 * a * 4 / 3 * B + 10m
A * b = 8 / 9 * a * B + 10m
A * b = 90m
The hound has to run at least 90 meters to catch up with the hare!
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