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Finding the Fourth Proportional to 405.72, 609.39 and 251.91

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Solution

The fourth proportional to 405.72, 609.39 and 251.91 is: 378.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.72 : 609.39 = 251.91 : x
  2. Step 2: Convert to fraction form
    405.72/609.39 = 251.91/x
  3. Step 3: Cross multiply
    405.72x = 609.39 × 251.91
  4. Step 4: Simplify right side
    405.72x = 153,511.43
  5. Step 5: Solve for x
    x = 153,511.43/405.72
  6. Step 6: Final answer
    x = 378.37

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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.