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Finding the Fourth Proportional to 418.68, 628.04 and 213.20

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Solution

The fourth proportional to 418.68, 628.04 and 213.20 is: 319.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.68 : 628.04 = 213.20 : x
  2. Step 2: Convert to fraction form
    418.68/628.04 = 213.20/x
  3. Step 3: Cross multiply
    418.68x = 628.04 × 213.20
  4. Step 4: Simplify right side
    418.68x = 133,897.88
  5. Step 5: Solve for x
    x = 133,897.88/418.68
  6. Step 6: Final answer
    x = 319.81

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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.