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Finding the Fourth Proportional to 280.32, 419.84 and 206.72

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Solution

The fourth proportional to 280.32, 419.84 and 206.72 is: 309.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.32 : 419.84 = 206.72 : x
  2. Step 2: Convert to fraction form
    280.32/419.84 = 206.72/x
  3. Step 3: Cross multiply
    280.32x = 419.84 × 206.72
  4. Step 4: Simplify right side
    280.32x = 86,789.32
  5. Step 5: Solve for x
    x = 86,789.32/280.32
  6. Step 6: Final answer
    x = 309.61

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.