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Finding the Fourth Proportional to 280.32, 387.32 and 206.88

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Solution

The fourth proportional to 280.32, 387.32 and 206.88 is: 285.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.32 : 387.32 = 206.88 : x
  2. Step 2: Convert to fraction form
    280.32/387.32 = 206.88/x
  3. Step 3: Cross multiply
    280.32x = 387.32 × 206.88
  4. Step 4: Simplify right side
    280.32x = 80,128.76
  5. Step 5: Solve for x
    x = 80,128.76/280.32
  6. Step 6: Final answer
    x = 285.85

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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.