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Finding the Fourth Proportional to 422.91, 630.69 and 387.47

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Solution

The fourth proportional to 422.91, 630.69 and 387.47 is: 577.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    422.91 : 630.69 = 387.47 : x
  2. Step 2: Convert to fraction form
    422.91/630.69 = 387.47/x
  3. Step 3: Cross multiply
    422.91x = 630.69 × 387.47
  4. Step 4: Simplify right side
    422.91x = 244,370.30
  5. Step 5: Solve for x
    x = 244,370.30/422.91
  6. Step 6: Final answer
    x = 577.83

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.