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Finding the Fourth Proportional to 520.05, 780.03 and 211.92

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Solution

The fourth proportional to 520.05, 780.03 and 211.92 is: 317.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.05 : 780.03 = 211.92 : x
  2. Step 2: Convert to fraction form
    520.05/780.03 = 211.92/x
  3. Step 3: Cross multiply
    520.05x = 780.03 × 211.92
  4. Step 4: Simplify right side
    520.05x = 165,301.03
  5. Step 5: Solve for x
    x = 165,301.03/520.05
  6. Step 6: Final answer
    x = 317.85

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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.