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A candy company can sell fruit gums in rectangular boxes or in cylindrical tubes. Each box is 8 cm by 3 cm by 7 cm. Each cylinder has radius 3 cm and height 6 cm. The company wants the packaging that uses less material. Which packaging should the company choose? Justify your choice.

User Hellblazer
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1 Answer

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Answer:

i. The company should use the cylindrical tubes.

ii. This is because the surface area of the cylindrical tubes, A' = 169.65 cm² is less than the surface area of the rectangular box, A = 202 cm²

Explanation:

i, Which packaging should the company choose?

The packaging that uses less material is the one with the least surface area. So, we find the surface area of each material.

For the rectangular box, the surface area, A = 2(lb + lh + bh) where l = length, b = breadth and h = height. Since each box is 8 cm by 3 cm by 7 cm,l = 8 cm, b = 3cm and h = 7cm.

So, ,A = 2(lb + lh + bh)

,A = 2( 8 cm × 3 cm + 8 cm × 7 cm + 3 cm × 7cm)

A = 2(24cm + 56 cm + 21cm)

A = 2(101 cm²)

A = 202 cm²

For the cylindrical tube, the surface area, A' = 2πr(r + h) where r = radius of cylinder and h = height of cylinder.

Since each cylinder has radius 3 cm and height 6 cm, r = 3cm and h = 6 cm.

So, A' = 2πr(r + h)

A' = 2π(3 cm)(3 cm + 6cm)

A' = (6π cm)(9 cm)

A' = 54π cm²

A' = 169.65 cm²

Since the surface area of the cylindrical tubes, A' = 169.65 cm² is less than the surface area of the rectangular box, A = 202 cm²

The company should use the cylindrical tubes.

ii. Justify your choice.

This is because the surface area of the cylindrical tubes, A' = 169.65 cm² is less than the surface area of the rectangular box, A = 202 cm²

User SBF
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