answer
It takes two hours for Party A and Party B to complete the work together, 12 minutes.
A train must cross the first and second iron bridges at a speed of 600 meters per minute. It takes five seconds longer to cross the second iron bridge than the first one, and it is known that the length of the second iron bridge is 50 meters shorter than twice that of the first one. Try to find out the length of the two iron bridges respectively.
answer
The length of the first iron bridge is100m, and the length of the second iron bridge is150m.
Jiangnan Eco-food Processing Factory has purchased a batch of mountain products, the quality of which is, according to the market demand, for rough processing and fine processing. It is known that the quality of refined mountain products is more than twice that of roughing, and the quality of roughing mountain products is better.
answer
2000 kg