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Finding the Fourth Proportional to 418.86, 628.28 and 213.62

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Solution

The fourth proportional to 418.86, 628.28 and 213.62 is: 320.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.86 : 628.28 = 213.62 : x
  2. Step 2: Convert to fraction form
    418.86/628.28 = 213.62/x
  3. Step 3: Cross multiply
    418.86x = 628.28 × 213.62
  4. Step 4: Simplify right side
    418.86x = 134,208.96
  5. Step 5: Solve for x
    x = 134,208.96/418.86
  6. Step 6: Final answer
    x = 320.41

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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.