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Finding the Fourth Proportional to 686.07, 1,029.08 and 378.08

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Solution

The fourth proportional to 686.07, 1,029.08 and 378.08 is: 567.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.07 : 1,029.08 = 378.08 : x
  2. Step 2: Convert to fraction form
    686.07/1,029.08 = 378.08/x
  3. Step 3: Cross multiply
    686.07x = 1,029.08 × 378.08
  4. Step 4: Simplify right side
    686.07x = 389,067.53
  5. Step 5: Solve for x
    x = 389,067.53/686.07
  6. Step 6: Final answer
    x = 567.10

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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.