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Finding the Fourth Proportional to 425.22, 638.55 and 280.86

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Solution

The fourth proportional to 425.22, 638.55 and 280.86 is: 421.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    425.22 : 638.55 = 280.86 : x
  2. Step 2: Convert to fraction form
    425.22/638.55 = 280.86/x
  3. Step 3: Cross multiply
    425.22x = 638.55 × 280.86
  4. Step 4: Simplify right side
    425.22x = 179,343.15
  5. Step 5: Solve for x
    x = 179,343.15/425.22
  6. Step 6: Final answer
    x = 421.77

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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.