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Finding the Fourth Proportional to 520.08, 717.72 and 287.21

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Solution

The fourth proportional to 520.08, 717.72 and 287.21 is: 396.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.08 : 717.72 = 287.21 : x
  2. Step 2: Convert to fraction form
    520.08/717.72 = 287.21/x
  3. Step 3: Cross multiply
    520.08x = 717.72 × 287.21
  4. Step 4: Simplify right side
    520.08x = 206,132.77
  5. Step 5: Solve for x
    x = 206,132.77/520.08
  6. Step 6: Final answer
    x = 396.35

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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.