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Finding the Fourth Proportional to 406.26, 609.55 and 213.78

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Solution

The fourth proportional to 406.26, 609.55 and 213.78 is: 320.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    406.26 : 609.55 = 213.78 : x
  2. Step 2: Convert to fraction form
    406.26/609.55 = 213.78/x
  3. Step 3: Cross multiply
    406.26x = 609.55 × 213.78
  4. Step 4: Simplify right side
    406.26x = 130,309.60
  5. Step 5: Solve for x
    x = 130,309.60/406.26
  6. Step 6: Final answer
    x = 320.75

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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.