The circumference of the bottom surface of a cone-shaped rice pile is 12.56 meters, the height is 3 meters, and each cubic meter of rice weighs 500 kg, Write the formula clearly, I can't understand it!

The circumference of the bottom surface of a cone-shaped rice pile is 12.56 meters, the height is 3 meters, and each cubic meter of rice weighs 500 kg, Write the formula clearly, I can't understand it!

Bottom radius = 12.56 △ 2 △ 3.14 = 2m
Bottom area = 3.14 × 2 × 2 = 12.56 square meters
Volume = 12.56 × 3 △ 3 = 12.56 M3
Weight = 12.56 × 500 = 6280kg = 6.28t
Do not understand can ask!

The circumference of the bottom surface of a cone-shaped rice pile is 6.28 meters, 1.2 meters high, and each cubic meter of rice weighs 450 kg. How many kg does this pile of rice weigh?

Bottom radius = 6.28 △ 3.14 △ 2 = 1m
Volume = 1 × 1 × 3.14 × 1.2 × 1 / 3 = 1.256 M3
Mass = 1.256 × 450 = 502.4kg

0,38 square meters: () square decimeters

38 square decimeters