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Finding the Fourth Proportional to 520.39, 718.11 and 287.50

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Solution

The fourth proportional to 520.39, 718.11 and 287.50 is: 396.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.39 : 718.11 = 287.50 : x
  2. Step 2: Convert to fraction form
    520.39/718.11 = 287.50/x
  3. Step 3: Cross multiply
    520.39x = 718.11 × 287.50
  4. Step 4: Simplify right side
    520.39x = 206,456.63
  5. Step 5: Solve for x
    x = 206,456.63/520.39
  6. Step 6: Final answer
    x = 396.73

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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.