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Finding the Third Proportional to 399 and 681

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Solution

The third proportional to 399 and 681 is: 1,162.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    399 : 681 = 681 : x
  2. Step 2: Convert to fraction form
    399/681 = 681/x
  3. Step 3: Cross multiply
    399x = 681 × 681
  4. Step 4: Simplify right side
    399x = 463,761
  5. Step 5: Solve for x
    x = 463,761/399
  6. Step 6: Final answer
    x = 1,162.31

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Why These Related Problems?

These problems maintain the same ratio (1.71) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.