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Finding the Fourth Proportional to 520.72, 781.08 and 135.96

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Solution

The fourth proportional to 520.72, 781.08 and 135.96 is: 203.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.72 : 781.08 = 135.96 : x
  2. Step 2: Convert to fraction form
    520.72/781.08 = 135.96/x
  3. Step 3: Cross multiply
    520.72x = 781.08 × 135.96
  4. Step 4: Simplify right side
    520.72x = 106,195.64
  5. Step 5: Solve for x
    x = 106,195.64/520.72
  6. Step 6: Final answer
    x = 203.94

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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.