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Finding the Fourth Proportional to 280.28, 387.09 and 256.92

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Solution

The fourth proportional to 280.28, 387.09 and 256.92 is: 354.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.28 : 387.09 = 256.92 : x
  2. Step 2: Convert to fraction form
    280.28/387.09 = 256.92/x
  3. Step 3: Cross multiply
    280.28x = 387.09 × 256.92
  4. Step 4: Simplify right side
    280.28x = 99,451.16
  5. Step 5: Solve for x
    x = 99,451.16/280.28
  6. Step 6: Final answer
    x = 354.83

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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.