The distance from the liquid level of beer to the bottom of the bottle is10cm.

That is, the remaining wine is equivalent to the volume of a cylinder with a height of 10.

After inverted, the distance from the liquid level to the bottom of the bottle is15cm.

That is, the drunk wine is equivalent to the volume of a cylinder with a height of 15 cm.

Therefore, the ratio of the drunk wine to the remaining wine is:15:10 = 3: 2.

The remaining wine accounts for 2/(3+2)=2/5 of the total wine.

The remaining wine is: 750 * 2/5 = 300ml.

What our teacher said.

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