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Finding the Fourth Proportional to 686.08, 947.55 and 517.75

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Solution

The fourth proportional to 686.08, 947.55 and 517.75 is: 715.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.08 : 947.55 = 517.75 : x
  2. Step 2: Convert to fraction form
    686.08/947.55 = 517.75/x
  3. Step 3: Cross multiply
    686.08x = 947.55 × 517.75
  4. Step 4: Simplify right side
    686.08x = 490,594.01
  5. Step 5: Solve for x
    x = 490,594.01/686.08
  6. Step 6: Final answer
    x = 715.07

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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.