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Finding the Third Proportional to 399 and 539

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Solution

The third proportional to 399 and 539 is: 728.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    399 : 539 = 539 : x
  2. Step 2: Convert to fraction form
    399/539 = 539/x
  3. Step 3: Cross multiply
    399x = 539 × 539
  4. Step 4: Simplify right side
    399x = 290,521
  5. Step 5: Solve for x
    x = 290,521/399
  6. Step 6: Final answer
    x = 728.12

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Why These Related Problems?

These problems maintain the same ratio (1.35) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.