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Finding the Fourth Proportional to 686.43, 947.72 and 612.63

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Solution

The fourth proportional to 686.43, 947.72 and 612.63 is: 845.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.43 : 947.72 = 612.63 : x
  2. Step 2: Convert to fraction form
    686.43/947.72 = 612.63/x
  3. Step 3: Cross multiply
    686.43x = 947.72 × 612.63
  4. Step 4: Simplify right side
    686.43x = 580,593.90
  5. Step 5: Solve for x
    x = 580,593.90/686.43
  6. Step 6: Final answer
    x = 845.82

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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.