A rectangular wooden box is nine tenths of a meter long, two-thirds of a meter wide and one-third of a meter high. How to place this wooden box? What is the minimum floor area?

A rectangular wooden box is nine tenths of a meter long, two-thirds of a meter wide and one-third of a meter high. How to place this wooden box? What is the minimum floor area?

Because 9 / 10 > 2 / 3 > 1 / 3
Therefore, in order to minimize the floor area of wooden cases
It needs to be erected, with width and height touching the ground, area = width * height
=2/3 * 1/3
=2 / 9 (M2)

A bamboo pole is inserted into the pond. The part inserted into the pond sludge accounts for 1 / 5 of the total length. The part in the water is more than twice the part in the sludge. The length of the bamboo pole should be 1 meter

Let the length of bamboo pole be X
1/5 × x + 2/5 × x +1 =x
X = 2.5m

Two 1-meter-long bamboo poles are tied together. The part tied together is 20 cm. How long is the tied bamboo pole?

180 meters. The length of two pieces is 100 + 100 = 200 cm, minus the part tied together equals 200-20 = 180 cm
So the result is 180 cm. Sorry, my unit is wrong. It's cm. If it's right,