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Finding the Fourth Proportional to 609.77, 840.08 and 478.55

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Solution

The fourth proportional to 609.77, 840.08 and 478.55 is: 659.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.77 : 840.08 = 478.55 : x
  2. Step 2: Convert to fraction form
    609.77/840.08 = 478.55/x
  3. Step 3: Cross multiply
    609.77x = 840.08 × 478.55
  4. Step 4: Simplify right side
    609.77x = 402,013.69
  5. Step 5: Solve for x
    x = 402,013.69/609.77
  6. Step 6: Final answer
    x = 659.29

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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.