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The product of four integers a.b.c.d that don't want to be equal ABCD = 9, find a + B + C + D Mr. Wang sold two kinds of stocks at the same time. A made a profit of 20% when selling 1200 shares. B also made a loss of 20% when selling 1200 shares. Is the total profit or loss? When a plane flies between two cities, the wind speed is 244m / h. It takes 5 hours for downwind and 6 hours for headwind to find the distance between two cities There are two water inlet pipes in the pool, which are filled in 3 hours after opening a, 2 hours after opening b, and how many hours after opening both pipes? AB two runs, a lap 3 minutes, B lap 2 minutes at the same time running in the opposite direction, the first meeting in a few minutes?
1. The four numbers are - 3 - 1 1 3, so the sum is 0
2. The total price of 2400 A is 1200 / (1 + 20%) = 1000 B is 1200 / (1-20%) = 1500 a and 2500 B
2500-2400 = 100 profit 100
3. The total number of questions is 1
The speed of a and B water pipes is 1 / 3 and 1 / 2 respectively
1 / (1 / 3 + 1 / 2) = 6 / 5 = 1.2 hours
4. Set one circle as unit 1
The velocities of a and B are 1 / 3 and 1 / 2 respectively
1/(1/2+1/3)=6/5=1.2
Happy learning
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