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Finding the Fourth Proportional to 285.28, 391.11 and 280.09

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Solution

The fourth proportional to 285.28, 391.11 and 280.09 is: 383.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.28 : 391.11 = 280.09 : x
  2. Step 2: Convert to fraction form
    285.28/391.11 = 280.09/x
  3. Step 3: Cross multiply
    285.28x = 391.11 × 280.09
  4. Step 4: Simplify right side
    285.28x = 109,544.04
  5. Step 5: Solve for x
    x = 109,544.04/285.28
  6. Step 6: Final answer
    x = 383.99

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.