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Finding the Fourth Proportional to 609.06, 840.28 and 399.35

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Solution

The fourth proportional to 609.06, 840.28 and 399.35 is: 550.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.06 : 840.28 = 399.35 : x
  2. Step 2: Convert to fraction form
    609.06/840.28 = 399.35/x
  3. Step 3: Cross multiply
    609.06x = 840.28 × 399.35
  4. Step 4: Simplify right side
    609.06x = 335,565.82
  5. Step 5: Solve for x
    x = 335,565.82/609.06
  6. Step 6: Final answer
    x = 550.96

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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.