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What is the least number by which 30375 ...

What is the least number by which 30375 should be multiplied to get a perfect cube?

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To find the least number by which 30375 should be multiplied to obtain a perfect cube, we can follow these steps: ### Step 1: Prime Factorization First, we need to perform the prime factorization of the number 30375. 1. **Divide by 3**: - 30375 ÷ 3 = 10125 - 10125 ÷ 3 = 3375 - 3375 ÷ 3 = 1125 - 1125 ÷ 3 = 375 - 375 ÷ 3 = 125 - 125 is not divisible by 3, so we move to the next prime number (5). 2. **Divide by 5**: - 125 ÷ 5 = 25 - 25 ÷ 5 = 5 - 5 ÷ 5 = 1 So, the prime factorization of 30375 is: \[ 30375 = 3^5 \times 5^3 \] ### Step 2: Grouping the Factors Next, we need to group the factors into sets of three (since we are looking for a perfect cube). - The exponent of 3 in \(3^5\) is 5, which can be grouped as: - \(3^3\) (which is a perfect cube) and leaves \(3^2\) (which is not a perfect cube). - The exponent of 5 in \(5^3\) is 3, which is already a perfect cube. ### Step 3: Determine the Missing Factors To make the entire expression a perfect cube, we need to ensure that all prime factors have exponents that are multiples of 3. - For \(3^5\), we have \(5\) which is not a multiple of \(3\). We need \(3\) more \(3s\) to make it \(3^6\) (which is a perfect cube). - For \(5^3\), it is already a perfect cube. ### Step 4: Calculate the Least Number to Multiply Since we need one more \(3\) to make \(3^6\), we multiply by \(3\). Thus, the least number by which 30375 should be multiplied to get a perfect cube is: \[ \text{Least number} = 3 \] ### Final Answer The least number by which 30375 should be multiplied to get a perfect cube is **3**. ---
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