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Finding the Fourth Proportional to 609.38, 840.86 and 343.78

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Solution

The fourth proportional to 609.38, 840.86 and 343.78 is: 474.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.38 : 840.86 = 343.78 : x
  2. Step 2: Convert to fraction form
    609.38/840.86 = 343.78/x
  3. Step 3: Cross multiply
    609.38x = 840.86 × 343.78
  4. Step 4: Simplify right side
    609.38x = 289,070.85
  5. Step 5: Solve for x
    x = 289,070.85/609.38
  6. Step 6: Final answer
    x = 474.37

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.