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Finding the Fourth Proportional to 641.81, 961.32 and 487.81

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Solution

The fourth proportional to 641.81, 961.32 and 487.81 is: 730.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.81 : 961.32 = 487.81 : x
  2. Step 2: Convert to fraction form
    641.81/961.32 = 487.81/x
  3. Step 3: Cross multiply
    641.81x = 961.32 × 487.81
  4. Step 4: Simplify right side
    641.81x = 468,939.07
  5. Step 5: Solve for x
    x = 468,939.07/641.81
  6. Step 6: Final answer
    x = 730.65

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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.