Plastic stools in the dining room are neatly stacked together (pictured). According to the information in the picture, the height of 20 identical plastic stools stacked together neatly is calculated.
Set the table top thickness of plastic stool as xcm, and the height of legs as hcm.
3x+h=295x+h=35，
X = 3h = 20。
Then the height of 20 plastic stools stacked together neatly is 20+3× 20 = 80 (cm).
So the answer is: 80.