The most difficult math problem in the world o o o o o o o o o o o o o o o o o o o o o o o o Connect each circle with a straight line, not a diagonal line, not a blank line, not a cross line

The most difficult math problem in the world o o o o o o o o o o o o o o o o o o o o o o o o Connect each circle with a straight line, not a diagonal line, not a blank line, not a cross line

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The restaurant serves regular and special meals. The regular meal is 45 yuan and the special meal is 60 yuan. Today, 50 people come to the restaurant and pay 2790 yuan in total

Let X be the number of people who choose regular meals, then 45x + 60 (50-x) = 2790
The solution is x = 14

Math problem (formula answer)
For the first time, pour out 1 / 3 of a bottle of juice, then pour 40 ml back into the bottle. For the second time, pour out the remaining 5 / 9 of the bottle, and then pour out 180 ml, with the remaining 60 ml in the bottle. How many ml of the original juice in the bottle?

Before the second pour: (60 + 180) / (1-9 points 5) = 540ml
Original: (540-40) / (1-1 / 3) = 750ml