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How many distinct factors of 8000 are pe...

How many distinct factors of 8000 are perfect cubes.

A

12

B

6

C

8

D

4

Text Solution

AI Generated Solution

The correct Answer is:
To find how many distinct factors of 8000 are perfect cubes, we need to follow these steps: ### Step 1: Prime Factorization of 8000 First, we need to find the prime factorization of 8000. - 8000 can be expressed as \( 8000 = 8 \times 1000 \). - We know that \( 8 = 2^3 \) and \( 1000 = 10^3 = (2 \times 5)^3 = 2^3 \times 5^3 \). - Therefore, we can combine these: \[ 8000 = 2^3 \times (2^3 \times 5^3) = 2^{3+3} \times 5^3 = 2^6 \times 5^3 \] ### Step 2: Finding Perfect Cube Factors A factor is a perfect cube if all the exponents in its prime factorization are multiples of 3. From the prime factorization \( 8000 = 2^6 \times 5^3 \): - The exponent of 2 can be \( 0, 3, \) or \( 6 \) (these are the multiples of 3 that are less than or equal to 6). - The exponent of 5 can be \( 0 \) or \( 3 \) (these are the multiples of 3 that are less than or equal to 3). ### Step 3: Counting the Combinations Now we can count the combinations of these exponents: - For \( 2^x \): \( x \) can be \( 0, 3, 6 \) (3 choices). - For \( 5^y \): \( y \) can be \( 0, 3 \) (2 choices). To find the total number of distinct factors that are perfect cubes, we multiply the number of choices for \( x \) and \( y \): \[ \text{Total perfect cube factors} = \text{(choices for } x\text{)} \times \text{(choices for } y\text{)} = 3 \times 2 = 6 \] ### Final Answer Thus, the number of distinct factors of 8000 that are perfect cubes is **6**. ---
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