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Finding the Fourth Proportional to 609.15, 840.60 and 388.29

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Solution

The fourth proportional to 609.15, 840.60 and 388.29 is: 535.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.15 : 840.60 = 388.29 : x
  2. Step 2: Convert to fraction form
    609.15/840.60 = 388.29/x
  3. Step 3: Cross multiply
    609.15x = 840.60 × 388.29
  4. Step 4: Simplify right side
    609.15x = 326,396.57
  5. Step 5: Solve for x
    x = 326,396.57/609.15
  6. Step 6: Final answer
    x = 535.82

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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.