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Finding the Fourth Proportional to 405.19, 559.38 and 257.86

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Solution

The fourth proportional to 405.19, 559.38 and 257.86 is: 355.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.19 : 559.38 = 257.86 : x
  2. Step 2: Convert to fraction form
    405.19/559.38 = 257.86/x
  3. Step 3: Cross multiply
    405.19x = 559.38 × 257.86
  4. Step 4: Simplify right side
    405.19x = 144,241.73
  5. Step 5: Solve for x
    x = 144,241.73/405.19
  6. Step 6: Final answer
    x = 355.99

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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.