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Finding the Fourth Proportional to 418.90, 628.13 and 144.91

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Solution

The fourth proportional to 418.90, 628.13 and 144.91 is: 217.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.90 : 628.13 = 144.91 : x
  2. Step 2: Convert to fraction form
    418.90/628.13 = 144.91/x
  3. Step 3: Cross multiply
    418.90x = 628.13 × 144.91
  4. Step 4: Simplify right side
    418.90x = 91,021.59
  5. Step 5: Solve for x
    x = 91,021.59/418.90
  6. Step 6: Final answer
    x = 217.29

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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.