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Finding the Fourth Proportional to 487.40, 729.82 and 458.60

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Solution

The fourth proportional to 487.40, 729.82 and 458.60 is: 686.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.40 : 729.82 = 458.60 : x
  2. Step 2: Convert to fraction form
    487.40/729.82 = 458.60/x
  3. Step 3: Cross multiply
    487.40x = 729.82 × 458.60
  4. Step 4: Simplify right side
    487.40x = 334,695.45
  5. Step 5: Solve for x
    x = 334,695.45/487.40
  6. Step 6: Final answer
    x = 686.70

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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.