Please help. Thank you!

Mathematics

1 answer:

katrin2010 [14]3 years ago

3 0

Answer:

3a. ⇒ 2700 cm³

3b. ⇒ 72,900 cm³

3c. ⇒ 27

Step-by-step explanation:

3a.

∵ The model in a shape of square pyramid

∴ Its volume = base area × height

∵ Base shaped square with side length 15 cm

∴ Area of base = 15 × 15 = 225 cm²

∵ The model height = 12 cm

∴ She needs = 225 × 12 = 2,700 cm³ of plaster

3b.

∵ Each dimension in the actual stage = 3 times the model

∴ The side of the square base = 15 × 3 = 45 cm

∴ The height = 12 × 3 = 36 cm

∴ The area of the base = 45 × 45 = 2,025 cm²

∴ She needs = 2025 × 36 = 72,900 cm³ of plaster

3c.

∵ Each length in the actual stage is 3 times the model

∴ The volume of the actual stage = (3)³ the volume of the model

∴ The volume of the actual stage = 27 the volume of the model

To check your answer:

Volume actual ÷ Volume model = 72,900 ÷ 2700 = 27

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3 years ago

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Answer:

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Step-by-step explanation:

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