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Finding the Fourth Proportional to 686.20, 1,028.85 and 247.27

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Solution

The fourth proportional to 686.20, 1,028.85 and 247.27 is: 370.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.20 : 1,028.85 = 247.27 : x
  2. Step 2: Convert to fraction form
    686.20/1,028.85 = 247.27/x
  3. Step 3: Cross multiply
    686.20x = 1,028.85 × 247.27
  4. Step 4: Simplify right side
    686.20x = 254,403.74
  5. Step 5: Solve for x
    x = 254,403.74/686.20
  6. Step 6: Final answer
    x = 370.74

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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.