To make a cuboid tin bucket without cover, the bottom is a square with side length of 0.4 meters and the height of the bucket is 0.8 meters. At least how many square meters of tin is needed?

To make a cuboid tin bucket without cover, the bottom is a square with side length of 0.4 meters and the height of the bucket is 0.8 meters. At least how many square meters of tin is needed?

0.4×0.4 + 0.4×4×0.8
=0.16 + 1.28
=1.44 square meters

A cylindrical bucket without a cover has a circumference of 25.12dm at the bottom and a height of 1.2m. How many square decimeters of iron sheet is needed to make the bucket? How many liters is its volume?

1.2m=12dm
Iron sheet
﹙25.12÷3.14÷2﹚²×3.14＋25.12×12=50.24+301.44=351.68dm²
Volume? L
﹙25.12÷3.14÷2﹚²×3.14×12
=602.88dm³
=602.88 L

To make a pair of cylindrical uncovered iron buckets, the perimeter of the bottom is 12.56 decimeters, and the height is 6 decimeters. At least how many square decimeters of iron sheets should be used?

Bottom radius r = 12.56 / (3.14 * 2) = 2DM
The surface area of a pair of cylindrical uncovered metal buckets = [3.14 * 2 * 2 + 12.56 * 6] * 2 = 175.84 square decimeters
At least 175.84 square decimeters of iron sheet should be used