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Finding the Fourth Proportional to 418.49, 628.04 and 213.15

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Solution

The fourth proportional to 418.49, 628.04 and 213.15 is: 319.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.49 : 628.04 = 213.15 : x
  2. Step 2: Convert to fraction form
    418.49/628.04 = 213.15/x
  3. Step 3: Cross multiply
    418.49x = 628.04 × 213.15
  4. Step 4: Simplify right side
    418.49x = 133,866.73
  5. Step 5: Solve for x
    x = 133,866.73/418.49
  6. Step 6: Final answer
    x = 319.88

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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.