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Finding the Fourth Proportional to 521.60, 781.61 and 487.35

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Solution

The fourth proportional to 521.60, 781.61 and 487.35 is: 730.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.60 : 781.61 = 487.35 : x
  2. Step 2: Convert to fraction form
    521.60/781.61 = 487.35/x
  3. Step 3: Cross multiply
    521.60x = 781.61 × 487.35
  4. Step 4: Simplify right side
    521.60x = 380,915.20
  5. Step 5: Solve for x
    x = 380,915.20/521.60
  6. Step 6: Final answer
    x = 730.29

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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.