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To the south of the park, a 15 meter long, 24 centimeter wide and 3 meter high wall will be built. If 525 bricks are used per cubic meter, how many bricks are used in this wall?
24cm = 0.24M, 15 × 0.24 × 3 × 525, = 10.8 × 525, = 5670 (pieces). Answer: 5670 bricks are needed to build this wall
The reservoir is 20 m wide and 15 m high
If cement is applied to the bottom and all sides of the reservoir, how many square meters of cement is required?
A reservoir is 20m long, 15m wide and 3M high. If cement is applied to the bottom and around the reservoir, how many square meters of cement is required?
The bottom area is 20 * 15 = 300 square meters
Width times height, length times height are 4 sides (20 * 3 + 15 * 3) * 2 = 210 square meters
300 + 210 = 510 square meters
A: the area to be cemented is 510 square meters
If a stone tablet is 50cm long, 20cm wide, 3M high and 0.75T in weight, its volume is______ M3, its density is______ kg/m3．
The volume of the stone tablet: v = 0.5m × 0.2m × 3M = 0.3m3, the density of the stone tablet: ρ = MV = 0.75 × 103kg, 0.3m3 = 2.5 × 103kg / m3
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