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Finding the Fourth Proportional to 520.85, 781.34 and 323.39

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Solution

The fourth proportional to 520.85, 781.34 and 323.39 is: 485.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.85 : 781.34 = 323.39 : x
  2. Step 2: Convert to fraction form
    520.85/781.34 = 323.39/x
  3. Step 3: Cross multiply
    520.85x = 781.34 × 323.39
  4. Step 4: Simplify right side
    520.85x = 252,672.02
  5. Step 5: Solve for x
    x = 252,672.02/520.85
  6. Step 6: Final answer
    x = 485.12

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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.