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Finding the Fourth Proportional to 686.39, 1,029.40 and 247.57

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Solution

The fourth proportional to 686.39, 1,029.40 and 247.57 is: 371.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.39 : 1,029.40 = 247.57 : x
  2. Step 2: Convert to fraction form
    686.39/1,029.40 = 247.57/x
  3. Step 3: Cross multiply
    686.39x = 1,029.40 × 247.57
  4. Step 4: Simplify right side
    686.39x = 254,848.56
  5. Step 5: Solve for x
    x = 254,848.56/686.39
  6. Step 6: Final answer
    x = 371.29

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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.