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Finding the Fourth Proportional to 405.20, 559.19 and 257.83

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Solution

The fourth proportional to 405.20, 559.19 and 257.83 is: 355.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.20 : 559.19 = 257.83 : x
  2. Step 2: Convert to fraction form
    405.20/559.19 = 257.83/x
  3. Step 3: Cross multiply
    405.20x = 559.19 × 257.83
  4. Step 4: Simplify right side
    405.20x = 144,171.87
  5. Step 5: Solve for x
    x = 144,171.87/405.20
  6. Step 6: Final answer
    x = 355.81

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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.