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Finding the Fourth Proportional to 399.34, 550.77 and 305.85

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Solution

The fourth proportional to 399.34, 550.77 and 305.85 is: 421.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.34 : 550.77 = 305.85 : x
  2. Step 2: Convert to fraction form
    399.34/550.77 = 305.85/x
  3. Step 3: Cross multiply
    399.34x = 550.77 × 305.85
  4. Step 4: Simplify right side
    399.34x = 168,453.00
  5. Step 5: Solve for x
    x = 168,453.00/399.34
  6. Step 6: Final answer
    x = 421.83

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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.