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Finding the Fourth Proportional to 520.38, 718.08 and 287.49

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Solution

The fourth proportional to 520.38, 718.08 and 287.49 is: 396.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.38 : 718.08 = 287.49 : x
  2. Step 2: Convert to fraction form
    520.38/718.08 = 287.49/x
  3. Step 3: Cross multiply
    520.38x = 718.08 × 287.49
  4. Step 4: Simplify right side
    520.38x = 206,440.82
  5. Step 5: Solve for x
    x = 206,440.82/520.38
  6. Step 6: Final answer
    x = 396.71

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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.