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Finding the Fourth Proportional to 640.86, 885.12 and 430.68

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Solution

The fourth proportional to 640.86, 885.12 and 430.68 is: 594.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.86 : 885.12 = 430.68 : x
  2. Step 2: Convert to fraction form
    640.86/885.12 = 430.68/x
  3. Step 3: Cross multiply
    640.86x = 885.12 × 430.68
  4. Step 4: Simplify right side
    640.86x = 381,203.48
  5. Step 5: Solve for x
    x = 381,203.48/640.86
  6. Step 6: Final answer
    x = 594.83

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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.