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Finding the Fourth Proportional to 289.20, 430.09 and 280.09

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Solution

The fourth proportional to 289.20, 430.09 and 280.09 is: 416.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.20 : 430.09 = 280.09 : x
  2. Step 2: Convert to fraction form
    289.20/430.09 = 280.09/x
  3. Step 3: Cross multiply
    289.20x = 430.09 × 280.09
  4. Step 4: Simplify right side
    289.20x = 120,463.91
  5. Step 5: Solve for x
    x = 120,463.91/289.20
  6. Step 6: Final answer
    x = 416.54

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.