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Finding the Fourth Proportional to 721.90, 1,000.52 and 649

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Solution

The fourth proportional to 721.90, 1,000.52 and 649 is: 899.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.90 : 1,000.52 = 649 : x
  2. Step 2: Convert to fraction form
    721.90/1,000.52 = 649/x
  3. Step 3: Cross multiply
    721.90x = 1,000.52 × 649
  4. Step 4: Simplify right side
    721.90x = 649,337.48
  5. Step 5: Solve for x
    x = 649,337.48/721.90
  6. Step 6: Final answer
    x = 899.48

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.