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Finding the Fourth Proportional to 398.79, 550.27 and 221.73

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Solution

The fourth proportional to 398.79, 550.27 and 221.73 is: 305.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.79 : 550.27 = 221.73 : x
  2. Step 2: Convert to fraction form
    398.79/550.27 = 221.73/x
  3. Step 3: Cross multiply
    398.79x = 550.27 × 221.73
  4. Step 4: Simplify right side
    398.79x = 122,011.37
  5. Step 5: Solve for x
    x = 122,011.37/398.79
  6. Step 6: Final answer
    x = 305.95

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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.