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Finding the Fourth Proportional to 442.20, 609.90 and 284.72

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Solution

The fourth proportional to 442.20, 609.90 and 284.72 is: 392.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    442.20 : 609.90 = 284.72 : x
  2. Step 2: Convert to fraction form
    442.20/609.90 = 284.72/x
  3. Step 3: Cross multiply
    442.20x = 609.90 × 284.72
  4. Step 4: Simplify right side
    442.20x = 173,650.73
  5. Step 5: Solve for x
    x = 173,650.73/442.20
  6. Step 6: Final answer
    x = 392.70

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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.