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Finding the Fourth Proportional to 457.22, 686.12 and 213.76

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Solution

The fourth proportional to 457.22, 686.12 and 213.76 is: 320.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    457.22 : 686.12 = 213.76 : x
  2. Step 2: Convert to fraction form
    457.22/686.12 = 213.76/x
  3. Step 3: Cross multiply
    457.22x = 686.12 × 213.76
  4. Step 4: Simplify right side
    457.22x = 146,665.01
  5. Step 5: Solve for x
    x = 146,665.01/457.22
  6. Step 6: Final answer
    x = 320.78

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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.