A project was originally planned to have 35 workers and can be completed in 18 days. Now it is required to be completed three days in advance. How many more workers are needed?
35 × 18 divided by (18-3)
=630 divided by 15
=42 (person)
42-35 = 7 (person)
Seven more workers are needed
If the wind direction is eastward, the speed is 5 m / s. if the specified wind speed is + 5 m / s, the wind speed is - 23 m / s________
Known 2
The wind is westward and the speed is 23 m / s
x-2-x+4=2
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- 3. Party A and Party B go in the same direction from ab. they first meet at 700 meters away from a, and then continue to move forward. They meet again at 400 meters away from B to seek ab
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