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Finding the Fourth Proportional to 398.98, 550.58 and 221.93

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Solution

The fourth proportional to 398.98, 550.58 and 221.93 is: 306.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.98 : 550.58 = 221.93 : x
  2. Step 2: Convert to fraction form
    398.98/550.58 = 221.93/x
  3. Step 3: Cross multiply
    398.98x = 550.58 × 221.93
  4. Step 4: Simplify right side
    398.98x = 122,190.49
  5. Step 5: Solve for x
    x = 122,190.49/398.98
  6. Step 6: Final answer
    x = 306.26

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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.