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Finding the Fourth Proportional to 609.40, 840.52 and 388.12

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Solution

The fourth proportional to 609.40, 840.52 and 388.12 is: 535.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.40 : 840.52 = 388.12 : x
  2. Step 2: Convert to fraction form
    609.40/840.52 = 388.12/x
  3. Step 3: Cross multiply
    609.40x = 840.52 × 388.12
  4. Step 4: Simplify right side
    609.40x = 326,222.62
  5. Step 5: Solve for x
    x = 326,222.62/609.40
  6. Step 6: Final answer
    x = 535.32

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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.