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Finding the Fourth Proportional to 686.92, 947.96 and 407.30

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Solution

The fourth proportional to 686.92, 947.96 and 407.30 is: 562.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.92 : 947.96 = 407.30 : x
  2. Step 2: Convert to fraction form
    686.92/947.96 = 407.30/x
  3. Step 3: Cross multiply
    686.92x = 947.96 × 407.30
  4. Step 4: Simplify right side
    686.92x = 386,097.33
  5. Step 5: Solve for x
    x = 386,097.33/686.92
  6. Step 6: Final answer
    x = 562.07

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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.