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Finding the Fourth Proportional to 520.20, 717.84 and 287.31

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Solution

The fourth proportional to 520.20, 717.84 and 287.31 is: 396.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.20 : 717.84 = 287.31 : x
  2. Step 2: Convert to fraction form
    520.20/717.84 = 287.31/x
  3. Step 3: Cross multiply
    520.20x = 717.84 × 287.31
  4. Step 4: Simplify right side
    520.20x = 206,242.61
  5. Step 5: Solve for x
    x = 206,242.61/520.20
  6. Step 6: Final answer
    x = 396.47

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.