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Finding the Fourth Proportional to 429.71, 640.10 and 406.62

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Solution

The fourth proportional to 429.71, 640.10 and 406.62 is: 605.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.71 : 640.10 = 406.62 : x
  2. Step 2: Convert to fraction form
    429.71/640.10 = 406.62/x
  3. Step 3: Cross multiply
    429.71x = 640.10 × 406.62
  4. Step 4: Simplify right side
    429.71x = 260,278.48
  5. Step 5: Solve for x
    x = 260,278.48/429.71
  6. Step 6: Final answer
    x = 605.71

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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.