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Finding the Fourth Proportional to 686.35, 947.16 and 371.61

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Solution

The fourth proportional to 686.35, 947.16 and 371.61 is: 512.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.35 : 947.16 = 371.61 : x
  2. Step 2: Convert to fraction form
    686.35/947.16 = 371.61/x
  3. Step 3: Cross multiply
    686.35x = 947.16 × 371.61
  4. Step 4: Simplify right side
    686.35x = 351,969.75
  5. Step 5: Solve for x
    x = 351,969.75/686.35
  6. Step 6: Final answer
    x = 512.81

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.