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Answer the following three practical questions (the third one is based on proportional knowledge) 1. Hongxing primary school bought 135 meters of plastic rope skipping, and the swordsman made five rope skipping from 9 meters. According to this calculation, how many pieces of plastic rope can be made with the rest? 2. Dilute 400g of 8% sugar water with water to 5% sugar water. How many grams of water should be added? 3. A and B cars leave from two places 360 kilometers apart at the same time, and they run in opposite directions. They meet four hours later. The speed ratio of a and B cars is 2:3. How many kilometers per hour do a and B cars walk?
1. (135-9) / (9 / 5) = 70
2. Let x g of water be added. 400 * 8% = 32
32/400+x=5%
x=60
3. (2 + 3) * 4 = 20 copies
360 / 20 = 18 km
18 * 2 = 36 km
18 * 3 = 54 km
Car a 36, car B 54
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