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Finding the Fourth Proportional to 280.85, 387.57 and 257.62

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Solution

The fourth proportional to 280.85, 387.57 and 257.62 is: 355.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.85 : 387.57 = 257.62 : x
  2. Step 2: Convert to fraction form
    280.85/387.57 = 257.62/x
  3. Step 3: Cross multiply
    280.85x = 387.57 × 257.62
  4. Step 4: Simplify right side
    280.85x = 99,843.97
  5. Step 5: Solve for x
    x = 99,843.97/280.85
  6. Step 6: Final answer
    x = 355.50

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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.