A few math problems, very urgent! ① the current price of a dress is 33.4 yuan, which is 6.4 yuan cheaper than the original price. How much is the price reduction? ① The current price of a dress is 33.4 yuan, which is 6.4 yuan cheaper than the original price. How much is the price reduction? ② For a batch of grain, 40% of the total amount was transported in the first time and 112 packages were transported in the second time 75% of the total. How many packages are there in this batch of grain?

1、6.4/（33.4+6.4）=16%
2. 112 / (75% - 40%) = 320 packets

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