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Finding the Fourth Proportional to 399.54, 550.04 and 347.78

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Solution

The fourth proportional to 399.54, 550.04 and 347.78 is: 478.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.54 : 550.04 = 347.78 : x
  2. Step 2: Convert to fraction form
    399.54/550.04 = 347.78/x
  3. Step 3: Cross multiply
    399.54x = 550.04 × 347.78
  4. Step 4: Simplify right side
    399.54x = 191,292.91
  5. Step 5: Solve for x
    x = 191,292.91/399.54
  6. Step 6: Final answer
    x = 478.78

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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.