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Finding the Fourth Proportional to 520.95, 781.21 and 260.85

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Solution

The fourth proportional to 520.95, 781.21 and 260.85 is: 391.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.95 : 781.21 = 260.85 : x
  2. Step 2: Convert to fraction form
    520.95/781.21 = 260.85/x
  3. Step 3: Cross multiply
    520.95x = 781.21 × 260.85
  4. Step 4: Simplify right side
    520.95x = 203,777.32
  5. Step 5: Solve for x
    x = 203,777.32/520.95
  6. Step 6: Final answer
    x = 391.17

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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.