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Finding the Fourth Proportional to 686.10, 1,029.82 and 321.14

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Solution

The fourth proportional to 686.10, 1,029.82 and 321.14 is: 482.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.10 : 1,029.82 = 321.14 : x
  2. Step 2: Convert to fraction form
    686.10/1,029.82 = 321.14/x
  3. Step 3: Cross multiply
    686.10x = 1,029.82 × 321.14
  4. Step 4: Simplify right side
    686.10x = 330,716.39
  5. Step 5: Solve for x
    x = 330,716.39/686.10
  6. Step 6: Final answer
    x = 482.02

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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.