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Finding the Fourth Proportional to 609.07, 840.12 and 387.85

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Solution

The fourth proportional to 609.07, 840.12 and 387.85 is: 534.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.07 : 840.12 = 387.85 : x
  2. Step 2: Convert to fraction form
    609.07/840.12 = 387.85/x
  3. Step 3: Cross multiply
    609.07x = 840.12 × 387.85
  4. Step 4: Simplify right side
    609.07x = 325,840.54
  5. Step 5: Solve for x
    x = 325,840.54/609.07
  6. Step 6: Final answer
    x = 534.98

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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.