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Finding the Fourth Proportional to 686.20, 1,026.87 and 396.22

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Solution

The fourth proportional to 686.20, 1,026.87 and 396.22 is: 592.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.20 : 1,026.87 = 396.22 : x
  2. Step 2: Convert to fraction form
    686.20/1,026.87 = 396.22/x
  3. Step 3: Cross multiply
    686.20x = 1,026.87 × 396.22
  4. Step 4: Simplify right side
    686.20x = 406,866.43
  5. Step 5: Solve for x
    x = 406,866.43/686.20
  6. Step 6: Final answer
    x = 592.93

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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.