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Finding the Third Proportional to 399 and 812

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Solution

The third proportional to 399 and 812 is: 1,652.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    399 : 812 = 812 : x
  2. Step 2: Convert to fraction form
    399/812 = 812/x
  3. Step 3: Cross multiply
    399x = 812 × 812
  4. Step 4: Simplify right side
    399x = 659,344
  5. Step 5: Solve for x
    x = 659,344/399
  6. Step 6: Final answer
    x = 1,652.49

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Why These Related Problems?

These problems maintain the same ratio (2.04) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.