solve equations: x-(2/7)x=(1/14) For a batch of candy, 2 / 5 of the total candy has been packed. For another 21 kg, 3 / 4 of the total candy has been packed. How many kg are there in total? 2. The graduating class charges for photography. The number of students who have not paid is 1 / 7 of those who have already paid. Later, there are 2 people who have paid. At this time, the number of students who have not paid is 1 / 11 of those who have already paid. How many students are there in this class? Note that there must be a process!
①X=1/10
② Let the total number be x, then there is 2 / 5x + 21 = 3 / 4x, and the solution equation is x = 60kg
③ Suppose the number of people who pay money at first is x, then there is x + 1 / 7X = (x + 2) + (x + 2) / 11. Solving the equation: x = 42, then the total number of people = x + 1 / 7X = 48
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