Because it uses 1.2kg, and it is 1.2 times of the remaining oil. So the remaining oil is1.2/1.2 =1kg.

Plus 65438+ used 0.2kg. How many kilograms were there in the past? That is,1+1.2 = 2.2kg.

Question 2: The answer is x=6.

This is a simple linear equation. The teacher made no mistakes.

Step 1, remove the brackets and get: 18-6+8x= 10x.

Step 2: Move the right side of the equal sign by 8x to get: 12=2x.

So x=6.

Question 3: Answer: 12L and 1000 bottles.

30mL=0.03L Since a bottle is 0.03L, then 400 bottles are 0.03 * * 400 = 12l.

Second question: Since there are 30 liters, one * * can hold 30/0.03= 1000 bottles.

Question 4: Answer 3.2dm

80cm=8dm。

Now we know the length, width and volume.

Then the volume divided by the length and width is not high. That is 64/(2.5 * 8) = 3.2dm..

Many answers on the first floor are wrong. There is an error in unit conversion on the second floor. It should be 1dm= 10cm.