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Finding the Fourth Proportional to 280.69, 421.04 and 219.86

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Solution

The fourth proportional to 280.69, 421.04 and 219.86 is: 329.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.69 : 421.04 = 219.86 : x
  2. Step 2: Convert to fraction form
    280.69/421.04 = 219.86/x
  3. Step 3: Cross multiply
    280.69x = 421.04 × 219.86
  4. Step 4: Simplify right side
    280.69x = 92,569.85
  5. Step 5: Solve for x
    x = 92,569.85/280.69
  6. Step 6: Final answer
    x = 329.79

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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.