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Finding the Fourth Proportional to 630.49, 868.20 and 519.78

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Solution

The fourth proportional to 630.49, 868.20 and 519.78 is: 715.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.49 : 868.20 = 519.78 : x
  2. Step 2: Convert to fraction form
    630.49/868.20 = 519.78/x
  3. Step 3: Cross multiply
    630.49x = 868.20 × 519.78
  4. Step 4: Simplify right side
    630.49x = 451,273.00
  5. Step 5: Solve for x
    x = 451,273.00/630.49
  6. Step 6: Final answer
    x = 715.75

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.