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Finding the Fourth Proportional to 642.60, 961.47 and 487.98

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Solution

The fourth proportional to 642.60, 961.47 and 487.98 is: 730.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.60 : 961.47 = 487.98 : x
  2. Step 2: Convert to fraction form
    642.60/961.47 = 487.98/x
  3. Step 3: Cross multiply
    642.60x = 961.47 × 487.98
  4. Step 4: Simplify right side
    642.60x = 469,178.13
  5. Step 5: Solve for x
    x = 469,178.13/642.60
  6. Step 6: Final answer
    x = 730.12

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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.