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Finding the Fourth Proportional to 405.39, 558.46 and 280.83

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Solution

The fourth proportional to 405.39, 558.46 and 280.83 is: 386.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.39 : 558.46 = 280.83 : x
  2. Step 2: Convert to fraction form
    405.39/558.46 = 280.83/x
  3. Step 3: Cross multiply
    405.39x = 558.46 × 280.83
  4. Step 4: Simplify right side
    405.39x = 156,832.32
  5. Step 5: Solve for x
    x = 156,832.32/405.39
  6. Step 6: Final answer
    x = 386.87

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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.