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Finding the Fourth Proportional to 640.60, 961.38 and 434.68

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Solution

The fourth proportional to 640.60, 961.38 and 434.68 is: 652.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.60 : 961.38 = 434.68 : x
  2. Step 2: Convert to fraction form
    640.60/961.38 = 434.68/x
  3. Step 3: Cross multiply
    640.60x = 961.38 × 434.68
  4. Step 4: Simplify right side
    640.60x = 417,892.66
  5. Step 5: Solve for x
    x = 417,892.66/640.60
  6. Step 6: Final answer
    x = 652.35

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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.