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Finding the Fourth Proportional to 487.68, 730.86 and 429.78

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Solution

The fourth proportional to 487.68, 730.86 and 429.78 is: 644.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.68 : 730.86 = 429.78 : x
  2. Step 2: Convert to fraction form
    487.68/730.86 = 429.78/x
  3. Step 3: Cross multiply
    487.68x = 730.86 × 429.78
  4. Step 4: Simplify right side
    487.68x = 314,109.01
  5. Step 5: Solve for x
    x = 314,109.01/487.68
  6. Step 6: Final answer
    x = 644.09

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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.