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5. a) Identify 10 different rectangular prisms with whole-number dimensions that have a volume of 144 cm³. Show your work.

b) The volume of a rectangular prism with whole-number dimensions has a volume that is a prime number. What are its dimensions? Use an example to support your explanation.

User Sietschie
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2 Answers

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Final Answer:

a) Ten different rectangular prisms with whole-number dimensions that have a volume of 144 cm³ are:

1.
\( 1 * 1 * 144 \) cm³

2.
\( 1 * 2 * 72 \) cm³

3.
\( 1 * 3 * 48 \) cm³

4.
\( 1 * 4 * 36 \) cm³

5.
\( 1 * 6 * 24 \) cm³

6.
\( 1 * 8 * 18 \) cm³

7.
\( 1 * 9 * 16 \) cm³

8.
\( 1 * 12 * 12 \) cm³

9.
\( 2 * 2 * 36 \) cm³

10.
\( 2 * 3 * 24 \) cm³

b) The dimensions of a rectangular prism with whole-number dimensions and a volume that is a prime number could be
\( 1 * 1 * 144 \) cm³. For example, a rectangular prism with dimensions
\( 1 * 1 * 144 \)cm³ has a volume of 144 cm³, which is not a prime number.

Step-by-step explanation:

Certainly! Let's go through the detailed calculations for both parts of the question.

a) Identifying Rectangular Prisms with a Volume of 144 cm³:

To find rectangular prisms with a volume of 144 cm³ and whole-number dimensions, we need to consider the factors of 144 and arrange them into sets of three.

Factors of 144:

1.
\(1 * 1 * 144\) cm^3

2.
\(1 * 2 * 72\) cm^3

3.
\(1 * 3 * 48\) cm^3

4.
\(1 * 4 * 36\) cm^3

5.
\(1 * 6 * 24\) cm^3

6.
\(1 * 8 * 18\) cm^3

7.
\(1 * 9 * 16\) cm^3

8.
\(1 * 12 * 12\) cm^3

9.
\(2 * 2 * 36\) cm^3

10.
\(2 * 3 * 24\) cm^3

These combinations result in rectangular prisms with whole-number dimensions and a volume of 144 cm³.

b) Rectangular Prism with Whole-Number Dimensions and a Prime Volume:

The goal here is to find dimensions that result in a rectangular prism with a volume that is a prime number.

Incorrect example:
\(1 * 1 * 144\) cm³

Correct example:
\(2 * 2 * 36\) cm³

For the correct example, the calculations are as follows:


\[ \text{Volume} = \text{Length} * \text{Width} * \text{Height} \]


\[ \text{Volume} = 2 * 2 * 36 = 144 \, \text{cm³} \]

In this case, the volume is 144 cm³, which is not a prime number. Let me correct the example:

Corrected example:
\(2 * 2 * 36\) cm³

Now, the volume is 144 cm³, and the dimensions are whole numbers, but the volume is not a prime number. I apologize for the confusion in my previous responses.

User Mahozad
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Final answer:

Ten different rectangular prisms with a volume of 144 cm³ are identified. It is explained that a rectangular prism with a volume that is a prime number cannot have whole-number dimensions since prime numbers only have two distinct factors.

Step-by-step explanation:

The question involves finding different rectangular prisms with a specific volume and understanding the concept of volume in terms of whole numbers and prime numbers. We're asked to identify 10 different rectangular prisms with whole-number dimensions that have a volume of 144 cm³ and then consider the possibility of a prism with a prime number volume.

  • (1, 144, 1)
  • (2, 72, 1)
  • (3, 48, 1)
  • (4, 36, 1)
  • (6, 24, 1)
  • (8, 18, 1)
  • (9, 16, 1)
  • (12, 12, 1)
  • (3, 8, 6)
  • (4, 4, 9)

For part b, a rectangular prism with dimensions that yield a prime number volume is not possible since a volume is computed by multiplying the length, width, and height, and a prime number has only two distinct divisors: 1 and itself. Therefore, any non-unit dimensions multiplied together will result in a non-prime product.

An example supporting this explanation: Consider a prime number like 5. We cannot find whole number dimensions for a rectangular prism that multiply to 5 because this would require one of the factors to be 1 and the other two factors to be 5, which is not a whole number.

User Netmajor
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