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Finding the Fourth Proportional to 686.20, 1,029.30 and 682.15

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Solution

The fourth proportional to 686.20, 1,029.30 and 682.15 is: 1,023.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.20 : 1,029.30 = 682.15 : x
  2. Step 2: Convert to fraction form
    686.20/1,029.30 = 682.15/x
  3. Step 3: Cross multiply
    686.20x = 1,029.30 × 682.15
  4. Step 4: Simplify right side
    686.20x = 702,137.00
  5. Step 5: Solve for x
    x = 702,137.00/686.20
  6. Step 6: Final answer
    x = 1,023.23

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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.