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Finding the Fourth Proportional to 489.78, 735.21 and 477.90

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Solution

The fourth proportional to 489.78, 735.21 and 477.90 is: 717.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.78 : 735.21 = 477.90 : x
  2. Step 2: Convert to fraction form
    489.78/735.21 = 477.90/x
  3. Step 3: Cross multiply
    489.78x = 735.21 × 477.90
  4. Step 4: Simplify right side
    489.78x = 351,356.86
  5. Step 5: Solve for x
    x = 351,356.86/489.78
  6. Step 6: Final answer
    x = 717.38

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.