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Finding the Fourth Proportional to 487.89, 730.17 and 420.30

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Solution

The fourth proportional to 487.89, 730.17 and 420.30 is: 629.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.89 : 730.17 = 420.30 : x
  2. Step 2: Convert to fraction form
    487.89/730.17 = 420.30/x
  3. Step 3: Cross multiply
    487.89x = 730.17 × 420.30
  4. Step 4: Simplify right side
    487.89x = 306,890.45
  5. Step 5: Solve for x
    x = 306,890.45/487.89
  6. Step 6: Final answer
    x = 629.02

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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.