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A bus runs from city a to city B for 60 kilometers per hour. After 2 hours, a truck runs from city B to city a and meets the bus in 4 hours. At this time, the truck runs one third of the whole journey. How many kilometers are there between the two cities?
The bus took 2 + 4 = 6 hours
Travel: 6 × 60 = 360 km
1-1 / 3 = 2 / 3
Distance between the two cities: 360 △ 2 / 3 = 540km
A and B are traveling from AB and ab at the same time. They meet in 4.2 hours. It is known that the speed ratio of the two vehicles is 4:3. After the two vehicles meet, they continue to move forward. How many hours faster does a arrive at a than B arrive at B?
A and B are traveling from AB and ab at the same time. They meet in 4.2 hours. It is known that the speed ratio of the two vehicles is 4:3. After the two vehicles meet, they continue to move forward. How many hours faster does a arrive at a than B arrive at B?
The travel ratio of Party A and Party B is 4:3
That is, a line: 4 / 7, B line: 3 / 7
So the whole time of a line is: 4.2 / (4 / 7) = 7.35 hours
2 / (3 / 7) = 9.8 hours
So a fast: 9.8-7.35 = 2.45 hours
Two people: A and B start at the same time from place a and place B and walk towards each other. The first time they meet is 5km away from place a, and then they continue to walk. When they arrive at the two places, they return immediately. The second time they meet is 2km away from place B. Q: how many kilometers are there between the two places?
The first time they met, they made a total journey, and a made a journey of 5km
The second time they met, they made a total of three journeys, and a made a journey of 5 × 3 = 15 kilometers
At the same time, a line is more than 2 kilometers
The distance between a and B
5 × 3-2 = 13 km
Every two people who attended a party shook hands once, and all of them shook hands 10 times______ People go to the party
According to the equation, X (x-1) 2 = 10, the solution is X1 = 5, X2 = - 4. A: there are 5 people attending the party. So the answer is: 5
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